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PREFACE
PREFACE
In preparing this book the author had in mind the wants both of the student and the teacher. For the student’s use the more difficult portions, particularly that on the embryology, may be omitted. The work has grown in part out of the writer’s experience in class work. In instructing small classes in the anatomy and metamorphoses of insects, it was strongly felt that the mere dissection and drawing of a few types, comprising some of our common insects, were by no means sufficient for broad, thor
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POSITION OF INSECTS IN THE ANIMAL KINGDOM
POSITION OF INSECTS IN THE ANIMAL KINGDOM
Although the insects form but a single class of the animal kingdom, they are yet so numerous in orders, families, genera, and species, their habits and transformations are so full of instruction to the biologist, and they affect human interests in such a variety of ways, that they have always attracted more attention from students than any other class of animals, the number of entomologists greatly surpassing that of ornithologists, ichthyologists, or the special students of any other class, whi
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RELATIONS OF INSECTS TO OTHER ARTHROPODA
RELATIONS OF INSECTS TO OTHER ARTHROPODA
The insects by general consent stand at the head of the Arthropoda. Their bodies are quite as much complicated or specialized, and indeed, when we consider the winged forms, more so, than any other class of the branch, and besides this they have wings, fitting them for an aërial life. It is with little doubt that to their power of flight, and thus of escaping the attacks of their creeping arthropod enemies, insects owe, so to speak, their success in life; i.e. their numerical superiority in indi
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LITERATURE ON SCOLOPENDRELLA
LITERATURE ON SCOLOPENDRELLA
Newport, George. Monograph of the class Myriopoda, order Chilopoda. (Trans. Linn. Soc. xix, pp. 349–439, 1 Pl., 1845.) Menge, A. Myriapoden der Umgegend von Danzig. (Neuste Schriften der naturforsch. Gesell. Danzig. iv, 1851.) Ryder, John H. Scolopendrella as the type of a new order of articulates (Symphyla). (Amer. Nat., May, 1880, xiv, pp. 375, 376.) —— The structure, affinities, and species of Scolopendrella. (Proc. Acad. Nat. Soc. Phil., pp. 79–86, 1881, 2 Figs.) Packard, A. S. Scolopendrell
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INSECTA (HEXAPODA)
INSECTA (HEXAPODA)
We are now prepared to discuss the fundamental or essential characters of the insects, including the wingless subclass (Synaptera), and the winged (Pterygota). Diagnostic characters of insects. — Body consisting of not more than twenty-one segments, which are usually heteronomous or of unequal size and shape, arranged in three usually well-defined regions ; i.e. a head, thorax, and hind-body or abdomen. Head small and flattened or rounded, composed of not less than six segments, and bearing, bes
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1. EXTERNAL ANATOMY
1. EXTERNAL ANATOMY
The insects differ from other arthropods in that the body is divided into three distinct regions,—the head, thorax, and abdomen, the latter regions in certain generalized forms not always very distinctly differentiated. The body behind the head may also conveniently be called the trunk, and the segments composing it the trunk-segments. In insects the head is larger in proportion to the trunk than in other classes, notably the Crustacea; the thorax is usually slightly or somewhat larger than the
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LITERATURE ON THE EXTERNAL ANATOMY
LITERATURE ON THE EXTERNAL ANATOMY
Swammerdam, Johann. Biblia naturæ. (In Dutch, German, and English.) 1737–1738, fol., London, 1758, Pls. Réaumur, Réné Antoine Ferchault, de. Mémoires pour servir à l’histoire des insectes. i-iv, 4º, Paris, 1734–1742. Lyonet, Pieter. Traité anatomique de la chenille, qui ronge le bois de saule, etc. 4º, pp. xxii, 616. À la Haye, 1732. Tab. 18. —— Recherches sur l’anatomie et les metamorphoses de differentes espèces d’insectes. Ouvrage posthume, publié par M. W. de Haan. pp. 580, tab. 54, 1832. La
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THE HEAD AND ITS APPENDAGES
THE HEAD AND ITS APPENDAGES
Fig. 24. —Presumed larva of Nemoptera ( Necrophilus arenarius ), Pyramids of Egypt.—After Roux, from Sharp. While the head is originally composed of probably not less than six segments, these are in the adult insect fused together into a capsule or hard chitinous box, the epicranium , with no distinct traces of the primitive segments. The head contains the brain and accessory ganglia, the mouth or buccal cavity, also the air-sacs in many winged forms, and gives support to the external organs of
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LITERATURE ON THE EPIPHARYNX
LITERATURE ON THE EPIPHARYNX
Réaumur. Mémoires pour servir à l’histoire des insectes, v, 1740, p. 318, Pl. 28, Figs. 4, 7, 8, 9, 10, 11 l. Kirby and Spence. Intr. to entomology, iii, 1828, p. 457. De Geer. ii, 1778; v, 26, Fig. 11, M. Kirby and Spence. Pl. xii, Fig. 2 K. Latreille. Organisation extérieure des insectes, p. 184. (Quoted from Kirby and Spence.) Savigny. Mémoires sur les animaux sans vertèbres. Partie I re , 1816, p. 12. Walter, Alfred. Beiträge zur Morphologie der Schmetterlinge. Erster Theil. Zur Morphologie
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LITERATURE OF THE MOUTH-PARTS OR BUCCAL APPENDAGES
LITERATURE OF THE MOUTH-PARTS OR BUCCAL APPENDAGES
Savigny, Jules-César. Mémoires sur les animaux sans vertèbres. 1 re Part. Description et classification des animaux invertébrés et articulés, etc. Fasc. 1 re . Mém. 1–2. Théorie des organes de la bouche des crustacés et des insectes. 12 Pl., Paris, 1816, pp. 1–117. Gerstfeld, Georg. Ueber die Mundteile der saugenden Insekten. Dorpat, 1853. Olfers, Ernestus V. Annotationes ad anatomiam Podurarum. Berolini, 1862, 4 Pls. Gerstaecker, Carl Eduard Adolph. Zur Morphologie der Orthoptera amphibiotica.
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THE THORAX AND ITS APPENDAGES
THE THORAX AND ITS APPENDAGES
The middle region of the body is called the thorax, and in general consists of three segments, which are respectively named the prothorax , mesothorax , and metathorax (Figs. 88, 89, 98). Fig. 88. —External anatomy of Melanoplus spretus , the head and thorax disjointed. The thorax contains the muscles of flight and those of the legs, besides the fore intestine (œsophagus and proventriculus), as well as, in the winged insects, the salivary glands. In the more generalized orders, notably the Ortho
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LITERATURE ON LEGS AND FEET
LITERATURE ON LEGS AND FEET
MacLeay, W. S. On the structure of the tarsus in the tetramerous Coleoptera of the French entomologists. (Trans. Linn. Soc. London, xv, 1825, pp. 63–73.) Speyer, O. Untersuchung der Beine der Schmetterlinge. (Isis, 1843, pp. 161–207, 243–264.) Pokorsky Joravko, A. von. Quelques remarques sur le dernier article du tarse des Hyménoptères. (Bull. Soc. imp. Natur. Moscou, 1844, xvii, pp. 140–159. Ref. in Isis, 1848, v, p. 347.) Rossmassler, E. A. Das Bein der Insekten. (Aus der Heimath, 1860, 3 kap.
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LITERATURE OF LOCOMOTION (WALKING, ETC.)
LITERATURE OF LOCOMOTION (WALKING, ETC.)
Carlet, G. Sur le mode de locomotion des chenilles. (Compt, rend. Acad. Paris, 1888, cvii, pp. 131–134. Naturwiss. Rundschau, iii Jahrg., 1888, No. 42, p. 543.) —— De la marche d’un insecte rendu tetrapode par la suppression d’une paire de pattes. (Ibid., pp. 565, 566.) —— Sur la locomotion des insectes et des arachnides. (Ibid., 1879, T. 89, pp. 1124, 1125.) —— Ueber den Gang eines vierfüssig gemachten Insekts. (Naturwiss. Rundschau, viii Jahrg., 1888, pp. 666–667; Compt. rend. 1888, cvii.) Dem
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LITERATURE OF WALKING ON SMOOTH SURFACES
LITERATURE OF WALKING ON SMOOTH SURFACES
Blackwell, J. Remarks on the pulvilli of insects. (Trans. Linn. Soc. London, xvi, 1831, pp. 487–492, 767–770.) Lowne, B. T. On the so-called suckers of Dytiscus and the pulvilli of insects. (Trans. Roy. Micr. Soc., pp. 267–271, 1871, 1 Pl.) West, Tuffen. On certain appendages to the feet of insects subservient to holding or climbing. (Journ. of the Proceed. Linn. Soc. London, Zoölogy, vi, 1862, pp. 26–88.) Dewitz, H. Ueber die Fortbewegung der Tiere an senkrechten, glatten Flächen vermittelst ei
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LITERATURE ON THE WINGS
LITERATURE ON THE WINGS
Jurine, L. Nouvelle méthode de classer les Hyménoptères et les Dipterès. Genève, 1807, 4º pp. 319, 14 Pls. —— Observations sur les ailes des Hyménoptères. (Mém. acad. Turin, 1820, xxiv, pp. 177–214.) Latreille, P. A. De la formation des ailes des Insectes. (Mém. sur divers sujets de l’histoire naturelle des Insectes, etc. Paris, 1819. Fasc. 8.) —— De quelques appendices particuliers du thorax de divers Insectes. (Mém. du Mus. d’Hist. nat., 1821, vii, pp. 1–21, 354–363.) Chabrier, J. Essai sur le
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LITERATURE ON FLIGHT
LITERATURE ON FLIGHT
Marey, E. J. La machine animale. Locomotion terrestre et aërienne. Paris, 1874. —— Mémoire sur le vol des insectes et des oiseaux. (Annal. Scienc. natur., 5 sér., Zool. xii, 1869, pp. 49–150; 5 sér., Zool. xv, 1872, 42 Figs.) —— Note sur le vol des insectes. (Compt. rend. et Mém. Soc. d. Biol. Paris, 4 sér., v, 1869, C. R. pp. 136–139.) —— Recherches sur le mécanisme du vol des insectes. (Journal de l’Anatomie et de la Physiologie, 6 Année, 1869, pp. 19–36, 337–348.) —— Animal mechanism. New Yor
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THE ABDOMEN AND ITS APPENDAGES
THE ABDOMEN AND ITS APPENDAGES
Fig. 176. —Abdomen of Termes flavipes : 1–10, the ten tergites; 1–9, the nine urites; c , cercopod. Fig. 177. —End of abdomen of Panorpa debilis drawn out, the chitinous pieces shaded: L , lateral, D , dorsal view; c , jointed cercopoda.—Gissler del. In the abdomen the segments are more equally developed than elsewhere, retaining the simple annular shape of embryonic life, and from their generalized nature their number can be readily distinguished (Fig. 176). The tergal and sternal pieces of eac
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LITERATURE ON THE ABDOMEN AND ITS APPENDAGES
LITERATURE ON THE ABDOMEN AND ITS APPENDAGES
Cornelius, C. Beiträge zur naheren Kenntnis von Palingenia longicauda . (Programm d. Real- u. Gewerbeschule zu Elberfeld, 1848, pp. 1–38, 4 Taf.) Schiödte, J. G. Bemerkungen über Myrmecophilen. Ueber den Bau des hinterleibes bei einigen Käfergattungen. (Germar’s Zeits. f. Ent., 1844.) —— De metamorphosi Eleutheratorum observationes. (Naturhist. Tidsskr. i-xiii, 1861–1883.) Meinert, F. Anatomia Forficularum. Anatomisk undersogelse af de Danske Orentviste, i. (Naturhist. Tidsskr. 3 raekke, ii, 186
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THE ARMATURE OF INSECTS: SETÆ, HAIRS, SCALES, TUBERCLES, ETC.
THE ARMATURE OF INSECTS: SETÆ, HAIRS, SCALES, TUBERCLES, ETC.
Fig. 208. —Larva of Dryocampa rubicunda , stage II.—Bridgham del. The cuticula. —The integument is externally either smooth and shining or variously punctured, granulated, tuberculated, striated, or hairy. In certain orders the skin is clothed with flattened setæ or scales, while many forms, as some caterpillars (Figs. 208, 209), beetles (Fig. 210), etc., are protected by spines, horns, etc., these in adult insects often forming secondary sexual characters, usually being more developed in the ma
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LITERATURE
LITERATURE
Leydig, Franz. Zum feineren Bau der Arthropoden. (Müller’s Archiv f. Anat. und Phys., 1855, pp. 376–480.) Fobel, Auguste. Les fourmis de la Suisse. Bâle, 1874. Saunders, Edward. Remarks on the hairs of some of our British Hymenoptera. (Trans. Ent. Soc. London, 1878, pp. 169–171.) Perez, J. Notes d’apiculture. (Bull. Soc. d’Apic. de la Gironde, Bordeaux, 1882.) Osten Sacken, C. R. von. An essay on comparative chætotaxy, or the arrangement of characteristic bristles of Diptera. (Trans. Ent. Soc. L
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THE COLORS OF INSECTS
THE COLORS OF INSECTS
The colors and bright markings of insects, especially those of butterflies, render them the most brilliant and beautiful creatures in existence, rivalling and even excelling the gay hues of our most splendidly colored birds. The subject has been but recently taken up and is in a somewhat crude condition, but the leading features have been roughly sketched out by the work of a few observers from a physical, chemical, and biological point of view. The colors of insects, as of all other animals, ar
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LITERATURE
LITERATURE
Heer, O. Einfluss des Alpenklimas auf die Farbe der Insecten. (Froebel u. Heer, Mitth. aus dem Gebiete der theoret. Erdkunde, 1836, i, pp. 161–170.) Goureau. Mémoire sur l’irisation des ailes des insectes. (Ann. Soc. Ent. France, 2 sér., i, 1848, pp. 201–215.) Laboulbène, A., et M. Follin. Note sur la matière pulvérulente qui recouvre la surface du corps des Lixus et de quelques autres insectes. (Ann. Soc. Ent. de France, 1848, vi, pp. 301–305, Fig.) Coquerel, Ch. Note sur la prétendue poussière
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THE MUSCULAR SYSTEM
THE MUSCULAR SYSTEM
In its general arrangement the muscular system of insects corresponds to the segmented structure of the body. Of the muscles belonging to a single segment, some extend from the front edge of one segment to that of the next behind it, and others to the hinder edge; there are also sets of dorsal and ventral muscles passing in an oblique or vertical course (Figs. 16–18). As Lang observes, “the greater part of the muscles of the body can be traced back to a paired system of dorsal and ventral inters
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LITERATURE ON THE MUSCLES
LITERATURE ON THE MUSCLES
Lyonet, P. Traité anatomique de la chenille. La Haye, 1762. Cornalia, E. Monographia del Bombyce del gelso. (Mem. R. Instituto Lombardo Sc. Lett. ed Arte, 1856.) Basch, S. Skelett und Muskeln des Kopfes von Termes. (Zeitschr. f. wissens. Zool., xv, 1865, pp. 55–75, 1 Taf.) Lubbock, John. Arrangement of the cutaneous muscles of the larva of Pygæra bucephala . London, 1858. 2 Pls. —— On some points in the anatomy of ants. (Month. Micr. Journ., xviii, pp. 121–142, 1877, 4 Pls.) —— On the anatomy of
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THE NERVOUS SYSTEM
THE NERVOUS SYSTEM
Fig. 239. —Central nervous system of Machilis maritima : au , eye; lo , optic tract; g , brain; an , antennal nerve; oe , œsophagus passing between the œsophageal commissures; usg , infraœsophageal ganglion; I-III, thoracic ganglia; 1–8, abdominal ganglia, the last ( Sabc ) consisting of three fused ganglia; s , sympathetic nervous system of the ventral cord.—After Oudemans, from Lang. The nervous system of insects consists of a double series or chain of ganglia connected by nervous cords or com
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LITERATURE ON THE NERVOUS SYSTEM
LITERATURE ON THE NERVOUS SYSTEM
Newport, George. On the nervous system of the Sphinx ligustri L., and on the changes which it undergoes during a part of the metamorphoses of the insect. (Phil. Trans. Roy. Soc., London, 1832, pp. 383–398; 1834, pp. 389–423, Pls.) Helmholtz, H. L. F. De fabrica systematis nervosi evertebratorum. Diss. in aug. Berolini, 1842. Blanchard, E. Recherches anatomiques et zoologiques sur le système nerveux des animaux sans vertèbres. Du système nerveux des insectes. (Annales des Sciences nat., Sér. 3, v
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THE SENSORY ORGANS
THE SENSORY ORGANS
Fig. 259. —Different forms of compound eyes. A , a bug (Pyrrhocoris). B , worker bee. C , drone. D , male Bibio, a holoptic insect.—From Judeich and Nitsche. Of the eyes of insects there are two kinds, the simple and the compound. Of the former there are usually three, arranged in a triangle near the top of the head, between the compound eyes (Fig. 259, B ). The compound or facetted eyes, which are usually round and prominent, differ much in size and in the number of facets. The number of facets
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LITERATURE ON THE EYES AND VISION
LITERATURE ON THE EYES AND VISION
Serres, Marcel de. Mémoires sur les yeux composés et les yeux lisses des insectes. Montpellier, 1813. Müller, Johannes. Zur vergleichenden Physiologie des Gesichtssinnes der Menschen und der Tiere. 8 Taf. Leipzig, 1826. —— Ueber die Augen des Maikäfers. (Meckel’s Archiv f. Anat. u. Phys., 1829, pp. 177–181; Ann. d. Sc. nat., 1829, sér. 1, xviii, pp. 108–112.) Dujardin, F. Sur les yeux simples ou stemmates des animaux articulés. (C. R. Acad. Sci., Paris, 1847, xxv, pp. 711–714.) Gottsche, C. M. B
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LITERATURE OF THE ORGANS OF SMELL
LITERATURE OF THE ORGANS OF SMELL
Réaumur, Réné Ant. de. Mémoires pour servir à l’histoire des insectes. Paris, 1734–42. (i, 283; ii, 224). Lesser, F. C. Insecto-theologia, 1740, p. 262. Roesel, A. J. Insektenbelustigungen, 1746, ii, p. 51. Reimarus, H. S. Allgemeine Betrachtung ueber die Triebe der Thiere hauptsächlich ihre Kunsttriebe (Instinct). Hamburg, 1760, p. 355. Sulzer, J. H. Die Kenntzeichen der Insecten. Zürich, 1761. Lyonet, P. Traité anatomique de la chenille, 1762, pp. 42, 96, 195. Comparetti, A. De aure interna co
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LITERATURE ON THE ORGANS OF TASTE
LITERATURE ON THE ORGANS OF TASTE
Meinert, F. Bidrag til de danske myrers naturhistorie. (Kgl. Dansk Vidensk. selsk. skrifter. Kjoebenhavn. Raekke 5 Naturvid. og math. Afd., v, 1861, pp. 273–340.) Wolff, O. J. B. Das Riechorgan der Biene. (Nova acta d. K. Leop.-Carol. Akad., xxxviii, 1875, pp. 1–251, 8 Taf.) Joseph, G. Zur Morphologie des Geschmacksorganes bei Insekten. (Amtlicher Bericht der 50. Versammlung deutscher Naturforscher und Aerzte in München, 1877, pp. 227–228.) Künckel et Gazagnaire. Du siège de la gustation chez le
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LITERATURE ON THE ORGANS OF HEARING
LITERATURE ON THE ORGANS OF HEARING
Siebold, C. Th. E. von. Ueber das Stimm- und Gehörorgan der Orthopteren. (Archiv f. Naturgesch., 1844, x, pp. 52–81.) Johnston, Christopher. Auditory apparatus of the culex mosquito. (Quart. Journ. Micr. Soc., 1855, iii, pp. 97–102, 1 Fig.) Hicks, Braxton. On a new organ in insects. (Journ. Linn. Soc. Zool., London, 1857, pp. 130–140, 1 Pl.) —— Further remarks on the organ found on the bases of the halteres and wings of insects. (Trans. Linn. Soc., London, 1857, xxii, pp. 141–145, 2 Pls.) Hensen
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THE DIGESTIVE CANAL AND ITS APPENDAGES
THE DIGESTIVE CANAL AND ITS APPENDAGES
Fig. 297. —Transverse section through an abdominal segment of larva of Megalopyge crispata , showing the relations of the digestive canal to the other organs: int , hind-intestine, with its mucous or epithelial layer ( ep ), and ml its outer or muscular layer; ng , ventral ganglion; ht , heart; mp , urinary tubes; f , fat-body; sc , thickened portion of the hypodermis ( hy ) containing the setigenous cells; m , muscles; m′ , a pair of retractor muscles inserted near the base of the lateral gland
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LITERATURE ON THE ORGANS OF DIGESTION
LITERATURE ON THE ORGANS OF DIGESTION
Treviranus, G. R. Resultate einiger Untersuchungen über den inneren Bau der Insekten. (Verdauungsorgane von Cimex rufipes .) (Annal. d. Wetterau. Gesells., 1809, i, pp. 169–177, 1 Taf.) Ramdohr, C. A. Abhandlungen über die Verdauungswerkzeuge der Insekten. 1811, vii, pp. 221, 30 Taf. Dutrochet, R. J. H. Mémoire sur les métamorphoses du canal alimentaire dans les insectes. (Journal de Physique, 1818, lxxxvi, pp. 130–135, 189–204; Meckel’s Archiv, 1818, iv, pp. 285–293.) Suckow, F. W. L. Verdauung
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LITERATURE ON THE PHYSIOLOGY OF DIGESTION
LITERATURE ON THE PHYSIOLOGY OF DIGESTION
Davy, J. Note on the excrements of certain insects, and on the urinary excrement of insects. (Edinburgh New Phil. Journ., 1846, xl, pp. 231–234, 335–340; 1848, xlv, pp. 17–29.) —— Some observations on the excrements of insects, in a letter addressed to W. Spence. (Trans. Ent. Soc. London, Ser. 2, iii, 1854, pp. 18–32.) Bouchardat, A. De la digestion chez le ver à soie. (Revue et Mag. de Zool., Sér. 2, 1851, iii, pp. 34–40.) Lacaze-Duthiers, H., et A. Riche. Mémoire sur l’alimentation de quelques
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THE GLANDULAR AND EXCRETORY APPENDAGES OF THE DIGESTIVE CANAL
THE GLANDULAR AND EXCRETORY APPENDAGES OF THE DIGESTIVE CANAL
Into each primary division of the digestive canal open important glands. The salivary and silk-glands are offshoots of the œsophagus (stomodæum); the cœcal appendages open into the stomach (mesenteron), while the urinary tubes grow out in embryonic life from the primitive intestine (proctodæum), and there are other small glands which are connected with the end of the hind-intestine. We will begin our account of these glands with those of the Orthoptera, where they are well developed. In the cock
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LITERATURE ON THE SALIVARY GLANDS
LITERATURE ON THE SALIVARY GLANDS
Leydig, F. Zur Anatomie der Insekten. (Archiv Anat. und Phys. 1859.) —— Untersuchungen zur Anatomie und Histiologie der Tiere. Bonn, 1883, pp. 174, 8 Taf. —— Intra- und interzellulare Gänge. (Biolog. Centralblatt, x, 1890, pp. 392–396.) Dohrn, A. Zur Anatomie der Hemipteren. (Stettin. Entom. Zeit., 1866, salivary glands, pp. 328–332.) Kupffer, C. Die Speicheldrüsen von Periplaneta orientalis und ihr Nervenapparat. (Beiträge zur Anatomie und Physiol., 1875.) Schiemenz, P. Ueber das Herkommen des
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LITERATURE ON THE SPINNING GLANDS
LITERATURE ON THE SPINNING GLANDS
Helm, E. Anatomische und histiologische Darstellung der Spinndrüsen der Schmetterlingsraupen. (Zeitschr. f. wissens. Zool., xxvi, 1876, pp. 434–469, 2 Taf.) Lidth de Jeude, Th. W. van. Zur Anatomie und Physiologie der Spinndrüsen der Seidenraupe. (Zool. Anzeiger, 1878, pp. 100–102.) Engelmann, W. Zur Anatomie und Physiologie der Spinndrüsen der Seidenraupe. (Onderz. Phys. Lab. Utrecht, iii, 1880, pp. 115–119.) Joseph, G. Vorläufige Mitteilung über Innervation und Entwickelung der Spinnorgane bei
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LITERATURE ON THE EXCRETORY (URINARY) ORGANS
LITERATURE ON THE EXCRETORY (URINARY) ORGANS
Malpighi, M. Dissertatio epistolica de Bombyce, Societati regiæ Londini ad scientiam naturalem promovendam institutæ dicata. (Londini, 1669, 12 Pls.) Herold, M. J. D. Entwicklungeschichte der Schmetterlinge. 1815. Rengger, J. R. Physiologische Untersuchungen über den tierischen Haushalt der Insekten. Tübingen, 1817, pp. 82. Wurzer. Chemische Untersuchungen des Stoffes in den Gallgefässen von Bombyx mori . (Meckel’s Archiv f. Physiol., iv, 1818, pp. 213–215.) Gaede, H. M. Physiologische Bemerkung
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LITERATURE ON THE SECRETORY GLANDS
LITERATURE ON THE SECRETORY GLANDS
Sirodot, S. Recherches sur les sécrétions chez les Insectes. (Ann. sc. nat., 4 Sér., Zool., 1858, x, pp. 141–189, 251–328, 12 Pls.) Gazagnaire, G. Des glandes chez les Insectes. (Compt. rend. Acad. Sc., Paris, 1886, cii, pp. 1501–1503; Annal. Soc. Ent. France, 1886, Bull., pp. 104–106.) Leydig, F. Beitrage zur Anatomie und Histiologie der Insekten. 1887. Hanow, Karl. Ueber Kerfabsonderungen und ihre Benutzung im eigenen Haushalte. (Programm des Realprogymnasiums zu Delitzsch für das Schuljahr 18
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DEFENSIVE OR REPUGNATORIAL SCENT-GLANDS
DEFENSIVE OR REPUGNATORIAL SCENT-GLANDS
While these eversible glands are not found in marine or aquatic arthropods such as Crustacea or Merostomata (Limulus), they are often present in the air-breathing forms, especially insects. In the winged insects they are of frequent occurrence, existing under great variety of form, varying greatly in position, and appearing usually to be in immediate relation with their active volant habits. Their presence is in direct adaptation to the needs and habits of their possessors, and being repellent,
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Distribution of repugnatorial or alluring scent-glands in insects[59]
Distribution of repugnatorial or alluring scent-glands in insects[59]
a. Each thoracic segment; sternal. Phryganea grandis. b. Prothoracic, sternal, discharging a lateral jet of spray; with a single large internal sack....
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LEPIDOPTERA
LEPIDOPTERA
Hyponomeuta evonymella. Bryophila , Cucullia formosa , C. scrophulariæ , Habrostola , Cleophana linariæ, Catocala (sp.), Aporia cratægæ , Aplecta nebulosa , Leucania staminea , L. hispanica , L. nonagrioides , Plusia gamma . Pheosia rimosa , Schizura concinna , Danima Banksii (Australia), Macrurocampa marthesia , Heterocampa pulverea , Cerura vinula , C. furcula , C. borealis , C. multiscripta. Probably all the species. c. Prothoracic, dorsal; sending out a V - shaped odoriferous organ (osmeteri
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LITERATURE ON DEFENSIVE OR REPUGNATORIAL GLANDS
LITERATURE ON DEFENSIVE OR REPUGNATORIAL GLANDS
Aldrovandus, U. De animalibus insectis libri septem cum singulorum iconibus ad vivum expressis. (Denuo impress: Bonon. apud Clementem Ferronium, 1638, p. 273. The first edition was in 1602.) Moufet, T. Insectorum sive minimorum animalium theatrum, etc. London, 1634, pp. 185, 186. Gœdart, J. Metamorphosis naturalis sive insectorum historia, etc. Amstelodami, 1700, Pars ii, p. 136. (French ed. of 1700, ii, p. 162; Lister’s Latin ed., London, 1685, p. 60.) Réaumur, R. A. F. Mémoires pour servir à l
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THE ALLURING OR SCENT-GLANDS
THE ALLURING OR SCENT-GLANDS
It is difficult to draw the line between repelling and alluring glands. Attention was first definitely called to the alluring odors of Lepidoptera by Fritz Müller, who showed that the males of certain butterflies are rendered attractive to the other sex by secreting odorous oils of the ether series. He pointed out that the seat of the odor is the androconia (see p. 199), while either repellent or pleasant odors are exhaled from abdominal glands. Those of Pieris napi yield a scent like that of ci
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LITERATURE ON ALLURING GLANDS
LITERATURE ON ALLURING GLANDS
Watson, J. On the microscopical examination of plumules, etc. (Ent. Month. Mag., ii, 1865, p. 1.) —— On certain scales of some diurnal Lepidoptera. (Mem. Lit. and Phil. Soc. Manchester, Ser. 3, ii, 1868, p. 63.) —— On the plumules or battledore scales of Lycænidæ. (Mem. Lit. and Phil. Soc. Manchester, Ser. 3, iii, 1869, p. 128.) Further remarks, etc. (Ibid., p. 259.) Anthony, J. Structure of battledore scales. (Month. Microsc. Journ., vii, 1872, p. 250; see also p. 200.) Morrison, Herbert Knowle
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THE ORGANS OF CIRCULATION
THE ORGANS OF CIRCULATION
Although Malpighi was the first to discover the heart in the young silkworm, it was not until 1826 that Carus proved that there was a circulation of blood in insects, which he saw flowing along each side of the body, and coursing through the wings, antennæ, and legs of the transparent larva of Ephemera, though three years earlier Herold demonstrated that the dorsal vessel of an insect is a true heart, pulsating and impelling a current of blood towards the head. This discovery was extended by Str
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LITERATURE ON THE HEART AND ON THE CIRCULATION OF THE BLOOD
LITERATURE ON THE HEART AND ON THE CIRCULATION OF THE BLOOD
Meckel, J. F. Ueber das Rückengefäss der Insekten. (Meckel’s Archiv, i, 1815, pp. 469–476.) Müller, J. G. De vasi dorsali Insectorum. Berolini, 1816, pp. 22. Serres, P. Marcel de. Observations sur les usages du vaisseau dorsal ou sur l’influence que le cœur exerce dans l’organisation des animaux articulés, etc. (Ann. du Mus. d’hist. nat., 1818, iv, pp. 149–192, 313–380, 2 Pls.; v, 1819, pp. 59–147, 1 Pl.) Herold. Physiologische Untersuchungen über das Rückengefäss der Insekten. (Schriften d. Ges
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THE BLOOD TISSUE
THE BLOOD TISSUE
Under this name Wielowiejski has included several important tissues or cellular bodies intimately concerned with the nutrition of the insect. These are:— In the body cavity of winged insects and of their larvæ occur yellowish masses of large cells filled with small drops of fat, and forming the “fat-body.” It is of various shapes, more or less lobulated or net-like, and covers or envelops parts of the viscera, also forming a layer under the integument (Fig. 143). The tracheal endings are usually
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LITERATURE ON PHOSPHORESCENCE
LITERATURE ON PHOSPHORESCENCE
Peters, W. Ueber das Leuchten der Lampyris italica . (Müller’s Archiv f. Anatomie, 1841, pp. 229–233.) Kölliker, A. Die Leuchtorgane von Lampyris, eine vorläufige Mittheilung. (Verhandl. d. phys. medizin. Gesellsch. Würzburg, 1857, viii, pp. 217–224.) Schultze, Max. Ueber den Bau der Leuchtorgane der Männchen von Lampyris splendidula . (Sitzber. d. niederrhein. Gesellsch. f. Natur. u. Heilkunde zu Bonn, 1864, Sep. p. 7.) —— Zur Kenntniss der Leuchtorgane von Lampyris splendidula . (Archiv f. mik
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THE RESPIRATORY SYSTEM
THE RESPIRATORY SYSTEM
While land vertebrates breathe by inhaling the air through the mouth into the lungs, insects respire by internal air-tubes ( tracheæ ), which ramify throughout every part of the body and its appendages. The air enters these tubes through a few openings, called spiracles or stigmata , arranged segmentally in the sides of the body. These tracheæ are everywhere bathed by the blood, and thus the latter is constantly aërated or kept fresh; the blood not, as in vertebrates or as in molluscs, seeking t
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LITERATURE ON THE ORGANS AND PHYSIOLOGY OF RESPIRATION
LITERATURE ON THE ORGANS AND PHYSIOLOGY OF RESPIRATION
Lyonet, P. Traité anatomique de la chenille qui ronge le bois du saule. (La Haye, 1760; 2d edit., La Haye, 1762, pp. 616, 18 Pls.) Treviranus, G. R. Beiträge zur Anatomie und Physiologie der Tiere und Pflanzen, 1816. —— Das organische Leben. Bremen, 1831. Rengger, J. R. Physiologische Untersuchungen über die tierische Haushaltung der Insekten. Tübingen, 1817. (Germar’s Mag. f. Ent., 1818, iii, pp. 410–413.) Dufour, L. Recherches anatomiques sur les Carabiques et sur plusieurs autres insectes Col
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THE ORGANS OF REPRODUCTION
THE ORGANS OF REPRODUCTION
Insects are without exception unisexual, the male and female organs existing in different individuals, no insects being normally hermaphroditic. The reproductive organs are situated in the hind-body or abdomen, especially near the end, the genital glands opening externally either in the space between the 7th and 8th, or 8th and 9th, or 9th and 10th abdominal segments, but as a rule between the 8th and 9th segments (Fig. 299). The primary or essential male organs are the testes, those of the fema
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LITERATURE ON THE ORGANS OF REPRODUCTION
LITERATURE ON THE ORGANS OF REPRODUCTION
Hunter, J. Observations of bees. (Phil. Trans. Roy. Soc. London, 1792, lxxxii, pp. 128–195.) Hegetschweiler, J. J. Dissertatio inauguralis zootomica de insectorum genitalibus. Turici, 1820, pp. 28, 1 Pl. Audouin, V. Recherches anatomiques sur la femelle du Drile jaunatre et sur le male de cette espèce. (Ann. Sc. nat., ii, 1824, pp. 443–462, 1 Pl.) Müller, Johannes. Ueber die Entwickelung der Eier im Eierstock bei den Gespenstheuschrecken. (Nova Acta Acad. Leop.-Carol., xii, 1825, pp. 555–672, 6
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a. The egg
a. The egg
Fig. 482. —Female Dyticus, laying eggs: A , ovipositor extended. B , egg of Notonecta, attached to stem of rush. C , egg of Dyticus, laid in excavation in rush.—After Régimbart, from Miall. Insects as a rule arise from eggs which are laid in a great variety of situations, those species which are viviparous being exceedingly few in number compared with the class as a whole. It is noteworthy that Leydig has found in the same Aphis, and even in the same ovary, an egg-tube producing eggs, while a ne
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b. Maturation or ripening of the egg
b. Maturation or ripening of the egg
Before the eggs of animals can be fertilized, they require in some observed cases, and probably in animals in general, to undergo a series of changes, which, as observed in the starfish, etc., consists in the replacement of the germinal vesicle by a very much smaller egg-nucleus, and also at the same time the construction at one pole of the egg of the directive or polar bodies (Fig. 502, r ). Towards the end of the ripening process of the insect egg this vesicle, according to Blochmann, passes t
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c. Fertilization of the egg
c. Fertilization of the egg
The egg next requires the penetration and admission into the yolk-interior of a spermatozoön. This process is essentially in insects, as in other animals, the fusion of the sperm-nucleus with the nucleus of the egg. Under normal conditions but a single spermatozoön is required for fertilization. As shown by Hertwig, in the sea-urchin, after the spermatozoön has penetrated into the egg, the head, and the small rounded body, called a centrosome , can still be recognized, but the tail becomes fused
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d. Division and formation of the blastoderm[80]
d. Division and formation of the blastoderm[80]
In insects as in most other Arthropoda the segmentation of the yolk is superficial and not total. The ovum is centrolicithal , i.e. the yolk is concentrated at the centre of the egg, and surrounded by a peripheral layer of transparent protoplasm (the Keimhautblastem ). Fig. 504. —Formation of the blastoderm of Pieris cratægi : A , longitudinal section through the egg, with two masses of protoplasm in the yolk. B , a blastoderm-cell at the upper end. C , a later stage, with more blastoderm-cells.
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e. Formation of the first rudiments of the embryo, and of the embryonic membranes
e. Formation of the first rudiments of the embryo, and of the embryonic membranes
Fig. 507. —Formation of the blastoderm in Hydrophilus: b , completed blastoderm; d , yolk; f , so-called division-cells; k , “keimhautblastem”; z , yolk-cells.—After Heider, from Korschelt and Heider. The embryo first arises as a whitish streak or band-like thickening on the ventral side of the egg, and is variously called the “primitive streak,” “primitive band,” “germinal band,” or “embryonal streak.” In most cases the primitive band is divided at regular intervals by transverse furrows, indic
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f. Formation of the external form of the body
f. Formation of the external form of the body
Origin of the body-segments. —As we have seen, the first traces of segments appear very early, the primitive band being divided by superficial transverse furrows into segments. This segmentation into arthromeres (somites or metameres) can be observed in Hydrophilus and Chalicodoma at a time when gastrulation begins (Figs. 515, 536). The segmentation extends not only across the median portion of the primitive band, through whose invagination the inner layer (endomesoderm) results, but also to the
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g. The appendages
g. The appendages
As we have seen, nearly or quite simultaneously all the limbs as a rule bud out from each side of the median line of the primitive band. They arise as saccular evaginations or outgrowths of the ectoderm, directed a little backwards. They are at first filled with mesoderm cells, and in the Orthoptera diverticula of the cœlom-sac are taken up into the rudimental limbs, as in Peripatus and Myriopoda. (Graber, Cholodkowsky.) As the antennæ, mouth-parts, legs, and abdominal appendages are all alike a
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h. Nervous system
h. Nervous system
The rudiments of the nervous and tracheal systems essentially contribute to the building up of the relief of the primitive band of insects. The nervous system is the earliest to appear, being indicated very early, in fact before the appendages begin to grow out. The first traces of the nervous system are two ridges extending along the primitive band, the depression between them being called the primitive furrow. At an early period the segmentation is observed in the primitive ridges, while widen
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i. Dorsal closure and involution of the embryonic membranes
i. Dorsal closure and involution of the embryonic membranes
Fig. 531. —Schematic figure of the formation of the dorsal tube by invagination of the dorsal plate (transformed serosa); following after stage Fig. 520, C , and Fig. 521, D ; am , amnion (now forming the provisional dorsal closure); r , dorsal tube, whose cells are already breaking away.—After Korschelt and Heider. In most other Arthropoda (Crustacea, Arachnida, Myriopoda, etc.) development goes on by the formation of a so-called primitive band, but without the appearance of peculiar embryonic
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j. Formation of the germ-layers
j. Formation of the germ-layers
Fig. 534. —Diagram showing the formation of the embryonic membranes in Lepidoptera ( A , after Kowalevsky, B and C , after Tichomiroff): k , primitive band; am , amnion: se , serosa; do , yolk; vd , invagination of the fore-gut, ed , of the hind-gut; m , mouth; an , anus; x , dorsal umbilical passage.—From Korschelt and Heider. The older views on the structure of the layers of the primitive band of insects were thoroughly unsatisfactory. Bütschli first found that in the bee, by a kind of folding
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k. Farther development of the mesoderm. Formation of the body-cavity
k. Farther development of the mesoderm. Formation of the body-cavity
We have seen that by means of an invagination extending throughout the entire length of the primitive band a layer of cells is produced which soon spreads out on the inner side of the band and thus forms a second lower (inner) layer (Fig. 539, C ). From this inner layer is separated at the anterior and posterior ends of the primitive band, the endoderm, which lies in direct contact with the invaginations of the proctodæum and stomodæum. The remainder, by far the most extensive part of the inner
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l. Formation of organs
l. Formation of organs
The nervous system. —As we have already seen (p. 554), the rudiments of the ventral nervous cord arise, after the gastrula invagination is completed, as two ectodermal thickenings situated on each side of the median line, the so-called primitive rolls or strips (Fig. 528, s ), which extend from the centre of the procephalic lobes of the head to the last segment, enclosing between them the single median “primitive groove” (Fig. 539, C , pr , and pw ). Soon after the appearance of the primitive st
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m. Length of embryonic life
m. Length of embryonic life
The duration of embryonic life varies greatly in different insects. The embryo of the blow-fly is fully developed in less than 24 hours, that of the house-fly in 24 hours. In the locusts and tree-cricket the embryos begin to develop at the end of the summer, continuing to grow until the cool weather of autumn, when growth is arrested, the later stages being finished in the latter part of the spring. It is so, likewise, with the embryos of many moths and other insects....
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n. The process of hatching
n. The process of hatching
This has been observed only in a few cases, and careful observations as to the exact manner in which the embryo breaks the egg-shell and frees itself from the amnion are much needed. Also the rapid changes of form from that of the embryo within the egg-shell, and that which it immediately assumes after breaking forth from the shell and membranes, have yet to be observed; for these will undoubtedly be found to have special phylogenetic significance. Indeed, the phylogenetic importance of the late
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LITERATURE ON EMBRYOLOGY
LITERATURE ON EMBRYOLOGY
Koelliker, Albert. Observationes de prima insectorum genesi, etc. Turici, 1842, pp. 29, 3 Pls. Rathke, H. Zur Entwickelungsgeschichte der Maulwurfsgrille ( Gryllotalpa vulgaris ). (Müller’s Archiv, 1844, ii, p. 27, Figs. 1–5.) Zaddach, G. Untersuchungen über die Entwicklung und den Bau der Gliederthiere. I. Die Entwicklung des Phryganideneies. Berlin, 1854, pp. 138, 5 Taf. —— Ueber die Entwicklung der Insekten. (Schrift, d. k. phys.-oekon. Gesell. Königsberg, viii Jahrg., 1867, Sitzb., p. 16.) L
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a. The nymph as distinguished from the larval stage
a. The nymph as distinguished from the larval stage
As there is no marked difference between the different stages of the young in the insects with an incomplete metamorphosis (Heterometabola), the chief difference being the possession of the rudiments of wings and the absence of a resting stage, the terms larva and pupa are in reality scarcely applicable to them, and we much prefer the term nymph , first proposed by Lamarck for the active “pupa” of Orthoptera, Hemiptera, the Odonata and Ephemeridæ, and adopted in part by many. Indeed, in the more
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b. Stages or stadia of metamorphosis
b. Stages or stadia of metamorphosis
The intervals or periods between the moults or ecdyses of caterpillars and other eruciform larvæ are called stages or stadia ; thus, as most caterpillars moult four times, we have five stages or stadia, or stage (stadium) I to V. As observed by Sharp, there is, unfortunately, no term in general use to express the form of the insect at the various stadia; “entomologists say, ‘the form assumed at the first moult,’ and so on.” Hence he adopts a term suggested by Fischer, [86] and calls the insect a
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c. Ametabolous and metabolous stages
c. Ametabolous and metabolous stages
In the Synaptera development is direct, the young differing neither in form, structure, or habits from the adult. Hence they are said to be ametabolous . Since there is an absence of even a tendency to a partial metamorphosis, it is evident that the insects have not inherited a tendency to undergo a transformation, but that it is an adaptation induced in the hexapod type after the first winged insects appeared, and which became more marked in the more specialized insects and at a period comparat
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THE LARVA
THE LARVA
The term larva is peculiarly applicable to the young of the holometabolous orders. The name (Latin, larva , a mask) was first given to the caterpillar because it was thought by the ancients to mask the form of the perfect insect. Swammerdam supposed that the larva contained within itself “the germ of the future butterfly, enclosed in what will be the case of the pupa, which is itself included in three or more skins, one over the other, that will successively cover the larva.” What led to his con
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LITERATURE ON ANCESTRY OF INSECTS, ETC.
LITERATURE ON ANCESTRY OF INSECTS, ETC.
Müller, Fritz. Für Darwin, 1869, pp. 144, 67 Figs. Brauer, Friedrich. Betrachtung ueber die Verwandlung der Insekten im Sinne der Descendenz-Theorie. (Verhandlung d. k.k. zool. bot. Gesell. Wien., 1869, 1 Taf., pp. 1–20.) Packard, A. S. Amer. Naturalist, iii, p. 45, March, 1869. —— Proc. Boston Soc. Nat. Hist., xiv, 1870, p. 61. —— Amer. Nat., iv, Feb. 1871, p. 756; v, 1871, pp. 52, 567. —— Embryological Studies. (Memoirs Peabody Acad. Sc. Salem, 1871–72.) —— Our common insects, 1873, Chapter on
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THE PUPA STATE
THE PUPA STATE
The word pupa is from the Latin meaning baby. Linnæus gave it this name from its resemblance to a baby which has been swathed or bound up, as is still the custom in Southern Europe. The term pupa should be restricted to the resting inactive stage of the holometabolous insects. Lamarck’s term chrysalis was applied to the complete or obtected pupa of Lepidoptera and of certain Diptera, and mumia , a mummy, to the pupæ of Coleoptera, Trichoptera, and most Hymenoptera. Latreille (1830) also restrict
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FORMATION OF THE PUPA AND IMAGO IN THE HOLOMETABOLOUS INSECTS (THE DIPTERA EXCEPTED)
FORMATION OF THE PUPA AND IMAGO IN THE HOLOMETABOLOUS INSECTS (THE DIPTERA EXCEPTED)
We have seen that in the incomplete metamorphosis, although there may be as many as five, and possibly seven moults, and in Chloëon as many as 20, and in Cicada septemdecim perhaps 25 or 30, there is but a slight change of form from one stage to another, and no period of inactivity. And this gradual outer transformation is so far as yet known paralleled by that of the internal organs, the slight successive changes of which do not differ from those observed in the growth of ametabolous insects. W
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DEVELOPMENT OF THE IMAGO IN THE DIPTERA
DEVELOPMENT OF THE IMAGO IN THE DIPTERA
The flies, particularly the Muscidæ and their allies (Brachycera), are the most highly modified of insects, their larvæ having undergone the greatest amount of reduction and loss of limbs, this atrophy involving even most of the head. The following account has been prepared in part from the works of Weismann, Ganin, Miall, and Pratt, but mostly from the excellent general summarized account given by Korschelt and Heider. In the holometabolic orders of insects, with their resting pupal stage, duri
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HYPERMETAMORPHISM
HYPERMETAMORPHISM
When an insect passes through more than the three normal stages of metamorphosis, i.e. the larval, pupal, and imaginal, it is said to undergo a hypermetamorphosis . The best-known examples are the supernumerary stages of Meloë, Stylops, etc. Fig. 637. —Hypermetamorphosis of male of Aspidiotus nerii : 1, freshly hatched larva; 2, larva shortly before pupating; b , rudiments of the legs; fl , of the wings; 3, pupa before moulting; 4, the same after moulting; 6, larva farther advanced than in 2; a
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SUMMARY OF THE FACTS AND SUGGESTIONS AS TO THE CAUSES OF METAMORPHISM
SUMMARY OF THE FACTS AND SUGGESTIONS AS TO THE CAUSES OF METAMORPHISM
An explanation of the causes of metamorphosis is one of the most difficult undertakings in biology, and the phenomenon has been considered as one of the chief difficulties in the way of the acceptance of the theory of descent. A review, however, of the facts of hypermetamorphism, particularly the life-history of Mantispa, throws much light on the subject, since it is very probable that the supernumerary stages and marked changes of form characterizing them are due to changes of environment, of h
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LITERATURE ON POSTEMBRYONIC DEVELOPMENT AND METAMORPHOSES
LITERATURE ON POSTEMBRYONIC DEVELOPMENT AND METAMORPHOSES
Herold, Moritz Johann David. Entwicklungsgeschichte der Schmetterlinge anatomisch und physiologisch bearbeitet. (Cassel, u. Marburg, 1815. 33 Taf., 4º, pp. 1–118, i-xxxiv.) Ratzeburg, F. T. C. Ueber Entwickelung des fusslosen Hymenopteren-larven, mit besonderer Rücksigt auf die Gattung Formica. (Nova Acta Natur. Curios., xvi, 1832, pp. 145–176.) Agassiz, Louis. The classification of insects from embryological data. (Smithsonian Contr., ii, Washington, 1851, pp. 28, 1 Pl.) Ganin, M. Beiträge zur
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