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Department of Zoology, Columbia University.
Department of Zoology, Columbia University.
Comparatively little has been done in this country upon marine Protozoa. A few observations have been made by Kellicott, Stokes, and Peck, but these have not been at all complete. With the exception of Miss Stevens's excellent description of species of Lichnophora I am aware of no single papers on individual forms. Peck ('93 and '95) clearly stated the economic position of marine Protozoa as sources of food, and I need not add to his arguments. It is of interest to know the actual species of var
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Genus AMŒBA Auct.
Genus AMŒBA Auct.
The pseudopodia are lobose, sometimes absent, the body then progressing by a flowing movement; the body consists of ectoplasm and endoplasm, the latter being granular and internal, the former hyaline and external. There is always one nucleus and one vacuole, but both may be more numerous. Reproduction takes place by division or by spore-formation. Fresh-water and marine. Amœba guttala Duj. Fig. 1. A minute form without pseudopodial processes, extremely hyaline in appearance, and characterized by
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Genus TRICHOSPHÆRIUM Schneider '78
Genus TRICHOSPHÆRIUM Schneider '78
Synonym: Pachymyxa hystrix Gruber. Marine rhizopods, globular or irregular in form, and slow to change shape. Dimorphic. Both forms multinucleate during vegetative life. Pseudopodia are long, thin, and thread-form, with rounded ends. Their function is neither food-getting nor locomotion, but probably tasting. The plasm of both forms is inclosed in a soft gelatinous membrane. In one form the jelly is impregnated with needles of magnesium carbonate (Schaudinn), but these are absent in the other fo
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Genus GROMIA Dujardin '35.
Genus GROMIA Dujardin '35.
The form is ovoid or globular, and the body is covered by a tightly fitting, plastic, chitin shell, which, in turn, is covered by a fine layer of protoplasm. The flexibility of the shell makes the form variable as in the amœboid types. The thickness of the shell is quite variable. The pseudopodial opening is single and terminal. The pseudopodia are very fine, reticulate, granular, and sharply pointed, and form a loose network outside of the shell opening. Nucleus single or multiple. Contractile
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Genus TRUNCATULINA D'Orbigny.
Genus TRUNCATULINA D'Orbigny.
A group of extremely variable foraminifera in which the shell is rotaline; i. e., involute on the lower side and revolute on the upper (Brady). The shell is calcareous and coarsely porous in older forms. The characters are very inconstant, and Brady gives up the attempt to distinguish the group by precise and constant characters. Truncatulina lobatula Walker & Jacob. Synonyms: See Brady '84 for a long list. "It is impossible to define by any precise characters the morphological range of
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Genus ACTINOPHRYS Ehr.
Genus ACTINOPHRYS Ehr.
The body is spherical and differentiated into granular endoplasm and vacuolated ectoplasm, but the zones are not definitely separated. There is one central nucleus and usually one contractile vacuole. The pseudopodia have axial filaments that can be traced to the periphery of the nucleus. Fresh and salt water. Actinophrys sol Ehr., variety. Fig. 5. Synonyms: See Schaudinn '95. The diameter is about 50µ; the vacuolated ectoplasm passes gradually into the granular endoplasm. This is the characteri
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Genus HETEROPHRYS Archer.
Genus HETEROPHRYS Archer.
The body is globular with but slight differentiation into ectoplasm and endoplasm; one nucleus in the latter; contractile vacuoles one or many; pseudopodia on all sides, thin, and with peripheral granule-streaming; surrounded by a globular, rather thick coat of jelly, which is hyaline inside and granular on the periphery. Fresh and salt water. Heterophrys myriapoda Archer. Fig. 6. Synonym: H. marina Hert. & Less. '74. Diameter 25 to 80µ; pseudopodia twice as long as the body diameter; th
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Genus MASTIGAMŒBA F. E. Schultze '75.
Genus MASTIGAMŒBA F. E. Schultze '75.
In general the form is oval and either regular in outline or irregular through the presence of many pseudopodia. One flagellum usually quite large and distinct. Differentiation of ectoplasm and endoplasm distinct or wanting. One to several contractile vacuoles. The pseudopodia are occasionally withdrawn, and the flagellum is the sole means of locomotion. In some cases the flagellum turns into a pseudopodium, and, conversely, the pseudopodium at one end may become a flagellum (see below). In some
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Genus CODONŒCA James Clark '66.
Genus CODONŒCA James Clark '66.
(Kent '81.) Small forms inclosed in cup or "house" of ovoid or goblet shape, colorless and probably gelatinous (chitin?) in texture, and borne upon a stalk. The monad does not completely fill the test. Contractile vacuole single, posterior. Codonœca gracilis, n. sp. Fig. 8. The cup is urn-shaped with a well-defined neck or collar borne upon a shoulder-like end of the body. It is hyaline, colorless, and carried upon a stalk equal in length to the cup or shorter than this. The animal does not fill
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Genus MONAS (Ehr.) Stein '78
Genus MONAS (Ehr.) Stein '78
The body is small, globular or oval and either free-swimming or fastened by one of the two flagella. The body is sometimes a little amœboid, with short pseudopodial processes. In addition to the main flagellum, there are usually one or two small flagella at the basis of the larger one. The nucleus is usually anterior, and one or two contractile vacuoles are present. Monas sp. Fig. 9. An extremely small form (3µ) attached by a thread of protoplasm—perhaps a flagellum, to algæ. The body is ovoid a
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Genus MONOSIGA Kent '81.
Genus MONOSIGA Kent '81.
Small colorless forms of Choanoflagellida, always naked and solitary. The posterior end is attached directly to the substratum, or there is a short stalk not exceeding the body in length. Kent '81 distinguished nine species, but Bütschli questioned the accuracy of many of these, and in this he was followed by Francé '97, who recognized three species— Monosiga ovata , M. fusiformis , and M. augustata . Fresh and salt water. Monosiga ovata S. Kent '81. Fig. 10. Synonyms: M. brevipes S. K.; M. cons
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Genus CODONOSIGA (Jas. Clark '67).
Genus CODONOSIGA (Jas. Clark '67).
This genus, as modified by Francé, is distinguished from the preceding by the possession of an unbranched stalk much longer than the body length. The body is naked and of various shapes, and the individuals are solitary or colonial upon a single stalk. Kent '81 enumerates no less than 10 species, which were cut down by Bütschli to 1. Francé admits 4— C. botrytis Jas. Clark; C. grossularia ; C. pyriformis , and C. furcata , all S. Kent—but regards the second and third as merely form varieties of
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Genus BODO (Ehr.) Stein.
Genus BODO (Ehr.) Stein.
The body is naked, usually amœboid in its changes, and provided with two flagella, one of which is usually trailed along under and behind the animal. The anterior end is usually pointed, with the flagella arising from a minute depression; the posterior end is rounded. Specific characters very difficult to analyze. Fresh and salt water. Bodo globosus Stein. Fig. 13. The body during movement is globular or ovoid, without any anterior process. The trailing flagellum is invariably much longer than t
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Genus OXYRRHIS Duj.
Genus OXYRRHIS Duj.
Medium-sized forms, somewhat oval in shape, with a rounded posterior end. The anterior end is continued dorsally in a somewhat attenuate pointed process. At the base of this process is a large cavity or funnel, on the dorsal wall of which, or on a projection from this wall, are two equal-size flagella. When at rest, the flagella are directed backwards. The nucleus is central. In moving, the posterior end is invariably in advance. This genus is exceptional among Mastigophora in that division is t
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Genus ASTASIA Ehr.
Genus ASTASIA Ehr.
Flagellates with one flagellum, a spindle-form body and a high degree of plasticity, the contour constantly changing. A distinct, usually striped cuticle is invariably present. "Eye-spots" are absent. Fresh and salt water. Astasia contorta Duj. Fig. 16. Astasia inflata Duj. '41. The body is colorless, transparent, and flexible. It is largest in the center, thence tapering at the two extremities. The surface of the cuticle is obliquely striated, giving to the animal a distinctly twisted appearanc
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Genus ANISONEMA Bütschli
Genus ANISONEMA Bütschli
Flagellates with two flagella, of which one is directed forwards and is concerned with the locomotion of the animal, while the other is directed backwards and drags after the animal when in motion. Body slightly compressed dorso-ventrally (fig. 17, section). An oral furrow is present on the ventral side and the two flagella originate in it (fig. 17, at left). The vacuole is on the left side. Food vacuoles are present in the posterior part. The nucleus is central. Movement creeping. Fresh and sal
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Genus DISTEPHANUS Stöhr.
Genus DISTEPHANUS Stöhr.
An aberrant flagellate bearing a single flagellum and a silicious skeleton resembling those of the Radiolaria. The skeleton consists of two rings of different diameter parallel with one another and connected by silicious bars. From the wider ring half a dozen bars radiate outwards and a similar number of short thorn-like bars point inwards obliquely. The color is yellow, and except for the flagellum the form might easily be mistaken for a Radiolarian, as has been the case repeatedly. Distephanus
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Genus EXUVIÆLLA Cienkowsky '82.
Genus EXUVIÆLLA Cienkowsky '82.
The form varies from globular to ovoid, with occasionally a sharp posterior end. Shells are usually somewhat compressed, and consist of two valves, which frequently slide one over the other in such a manner as to show the structure with great clearness. The right shell may have a distinct indentation in the anterior edge. There are two lateral, discoid, brown chromatophores, each of which possesses a central amylum granule. The nucleus is posterior. Salt water. Exuviælla lima Ehr. Fig. 18. Synon
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Genus GYMNODINIUM Stein '78.
Genus GYMNODINIUM Stein '78.
The general structure of these forms is similar to that of Glenodinium ; the most striking and positive difference is the absence of a shell. The animals are, as a rule, spherical, yet they may be pointed at the two ends or at one of them. They are also frequently flattened dorso-ventrally. The transverse furrow may be either circular and straight around the body or may describe a spiral course, passing even twice around the body. The flagella arise near cross-furrow or, in some cases, in longit
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Genus GLENODINIUM (Ehr.), Stein '83.
Genus GLENODINIUM (Ehr.), Stein '83.
Small globular forms with two distinct furrows, one transverse around the body, the other longitudinal upon the face only. The shell is soft and structureless with a distinct aperture near the meeting point of the two furrows. The endoplasm usually, but not always, contains a bright red eye-spot. Fresh and salt water. Glenodinium compressa , n. sp. Fig. 21, a, b, c. This species resembles G. acuminata of Ehrenberg except that it is strongly compressed laterally. The longitudinal furrow extends n
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Genus PERIDINIUM Ehr. '32, Stein '83.
Genus PERIDINIUM Ehr. '32, Stein '83.
The form is globular, ovoid or elongate, the apex frequently drawn out into a long tube. The transverse and longitudinal furrows are quite distinct, the former having often a spiral course about the body. The two halves of the body are similar, the posterior being somewhat shorter; the anterior half has seven equatorial plates, an oral plate, two lateral apical plates, and one or two dorsal plates. The two antapical plates frequently have a tooth-like process. The bodies are colorless, green or
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Genus CERATIUM (Schrank).
Genus CERATIUM (Schrank).
The general shape is a flattened sphere with three long processes or horns. The cross-furrow is either spiral or circular; the longitudinal furrow is usually wide and occupies the greater part of the anterior half of the shell. The shell is thick, reticulate or striped, and sometimes provided with short spines; often distinctly porous. The anterior half is composed of 3 equatorial and 3 apical plates, the latter being continued into the horn-like process. The posterior half is composed of 3 equa
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Genus AMPHIDINIUM Clap. & Lach.
Genus AMPHIDINIUM Clap. & Lach.
The body is ovoid to globular and usually much flattened dorso-ventrally. The anterior portion is very much reduced and is somewhat head-like or cap-like. The longitudinal furrow extends through the entire posterior body length and is apparently capable of widening and narrowing. It is probably naked (see here Klebs, Pouchet, Bütschli), although Stein maintained that there is a delicate cuticle-like shell. Chromatophores of brown or green colors present and usually grouped radially about a centr
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Genus LACRYMARIA Ehr. '30.
Genus LACRYMARIA Ehr. '30.
Body short to very long flask-shape; for the most part contractile, especially in the neck region. The posterior end is rounded or pointed. The main character is the mouth-bearing apex, which "sets like a cork in the neck of the flask." One or more circles of long cilia at the base of the mouth portion or upon it. The body is spirally striped. Contractile vacuole terminal, with sometimes one or two further forward. Macronucleus central, globular to elongate, sometimes double. Food mainly bacteri
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Genus TRACHELOCERCA (Ehr. '83) Cohn '66.
Genus TRACHELOCERCA (Ehr. '83) Cohn '66.
The only well-known representative is very elongate, large (up to 3 mm. Van Beneden), and very contractile. The main feature of importance in distinguishing it is the 4-part structure of the mouth region, which, however, may not be obvious. Pharynx faint and smooth. Contractile vacuole terminal. Macronucleus in one central body or in numerous pieces scattered throughout the cell. Salt water. Trachelocerca phœnicopterus Cohn '66. Fig. 30. Synonyms: T. sagitta Ehr. '40, Stein '59; T. tenuicollis Q
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Genus MESODINIUM Stein '62.
Genus MESODINIUM Stein '62.
The main part of the body is globular or conical, with a short, platform-like oral region, and a deep annular groove about the middle of the body. The œsophagus is rather long, and smooth or longitudinally striped. One or more rings of cirri rise in the groove. If more than one ring of cirri are present, the anterior set usually point forward and lie close to the anterior part of the body. The posterior set, on the other hand, cling close to the posterior region of the body and give to it a pecu
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Genus TIARINA R. S. Bergh '79.
Genus TIARINA R. S. Bergh '79.
Body subcylindrical, pointed posteriorly, two and one-half times as long as broad; encased in covering composed of separate pieces arranged in five girdles. The pieces bear processes which rest against neighboring pieces of the girdle. Mouth large, anus terminal near contractile vacuole. The macronucleus is simple and round. Salt water. Tiarina fusus (Cl. & Lach.) emend R. S. Bergh. Synonyms: Coleps fusus Cl. & Lach. '58; Daday '86; Möbius '88, Lauterborn '94; Shevyakov '86. This
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Genus LOXOPHYLLUM Dujardin '41.
Genus LOXOPHYLLUM Dujardin '41.
The body is flat and somewhat leaf-shape, flexible, and elastic. The anterior end is somewhat proboscis-like and flexible, but is not sharply demarcated as in Lionotus . The central portion of the body is developed into a more or less arched dorsal mass, which usually contains the nuclei and contractile vacuoles. As a result of this local thickening, the body is surrounded by a thin hyaline margin. This, however, may be absent on the right side in some species. The mouth reaches from the anterio
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Genus LIONOTUS Wrzesniowski '70.
Genus LIONOTUS Wrzesniowski '70.
The body is elongate and somewhat lance-shaped, widest at the central part and tapering to a point at the anterior end. The posterior end may be similarly tapered or rounded. The anterior end frequently proboscis-like, flat, and flexible, while the entire body is more or less elastic and contractile. The right side is flattened and alone provided with cilia, while the left side of the body proper is arched; on the left side of the proboscis is a row of coarse cilia resembling an adoral zone, and
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Genus NASSULA Ehr. '33
Genus NASSULA Ehr. '33
The body is ovoid or cylindrical, with well-rounded ends, and in some cases slightly flattened. The mouth is ventral and placed some distance from anterior end (1/4 to 1/3 total length). A slight depression on the ventral surface marks the mouth region, which is further indicated by larger and more powerful cilia. The rest of the body is uniformly ciliated. The entire body is marked by clearly defined spiral stripes. The mouth is circular and the œsophagus is supported by a considerable armature
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Genus CHILODON Ehr.
Genus CHILODON Ehr.
Small forms, greatly flattened dorso-ventrally and almost egg-form in outline. The anterior end is bent distinctly to the left and forms a characteristic process, which, together with the entire margin of the body, is soft and flexible. The posterior end is, as a rule, broadly rounded. The ventral surface is finely striate, and this surface alone is ciliated. The lines of cilia converge at the mouth, and at this region the cilia are somewhat larger and more distinct, thus forming a functional ad
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Genus DYSTERIA Huxley '57.
Genus DYSTERIA Huxley '57.
Small forms, firm in outline, and colorless or slightly colored. The body is somewhat clam-shaped, flattened, slightly curved or straight on the right side, the other more convex. The true ventral side is only a narrow strip along the right and anterior edge of the body, the apparent ventral side being a fold of the very large dorsal surface which comes around ventrally, forming a valved structure somewhat analogous to a clam shell. Cilia are limited to the outer edge of the small ventral surfac
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Genus FRONTONIA Ehr. (Cl. & Lach. '58?).
Genus FRONTONIA Ehr. (Cl. & Lach. '58?).
Form elongate and cylindrical, or often flattened dorso-ventrally, with round or pointed ends. It is usually plastic and contractile. Cilia are evenly distributed about the body and are similar in length. The large, open mouth lies on the anterior half of the ventral surface, and is elongate and oval in outline. On its left edge is a well-defined membrane which stretches across to the right side of the mouth. On the right edge is a small, longitudinally striped tract which is free from trichocys
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Genus COLPIDIUM Stein '60
Genus COLPIDIUM Stein '60
The general form is oval, slightly compressed laterally with the dorsal side strongly arched. The ventral side is slightly incurved. The anterior end is somewhat smaller than the posterior end, which is broadly rounded. The mouth is placed some distance from the anterior end in an oral depression and opens into a tubular œsophagus. There are usually two undulating membranes which do not extend beyond the mouth borders. The right undulating membrane extends down into the œsophagus and appears to
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Genus URONEMA Duj. '41.
Genus URONEMA Duj. '41.
Minute forms; colorless and constant in body form. The form is oval, slightly compressed on the ventral side, while the dorsal side is distinctly arched. The membrane is distinctly marked by rather widely separated striæ. These occasionally have a spiral course about the body; in all cases they can be easily counted. The mouth is large and placed near the center of the ventral surface. It is sometimes approached by a very shallow depression or peristome from the anterior end, and marked by two r
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Genus PLEURONEMA Dujardin '41.
Genus PLEURONEMA Dujardin '41.
Small to medium-sized ciliates, with an unchanging form. They are somewhat lens-shape and laterally compressed, the two surfaces about equally arched. The ventral surface is nearly straight or but slightly arched; the dorsal is quite convex. The anterior and posterior extremities are equally rounded. The peristome begins as a small depression, but becomes larger until it takes in nearly all of the ventral surface. The depression becomes much deeper at about the center of the body, and is especia
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Genus LEMBUS Cohn '66.
Genus LEMBUS Cohn '66.
Free-swimming animals of elongate form, more or less elastic, and flexible, bending readily to avoid obstacles, etc. The anterior half is usually drawn out into a slightly curved neck-like portion. The peristome is a small groove leading from the anterior end to the mouth about midway down the ventral side of the body. Bütschli, following Quennerstedt, describes an undulating membrane on each side of the peristome groove. Other observers, however, usually describe but one, the left, which is cle
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Genus ANOPLOPHRYA Stein '60.
Genus ANOPLOPHRYA Stein '60.
The general form is elongate, cylindrical or slightly flattened, with rounded ends, the posterior end tapering. The body is striated with clearly defined, often depressed lines, which run longitudinally and sometimes spirally. The contractile vacuoles are usually placed in rows upon the edges. The macronucleus is almost always long and band-formed, rarely oval, and generally extending through the entire length of the body. Micronuclei have been made out in one case. Reproduction is effected by s
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Genus CONDYLOSTOMA (KONDYLOSTOMA Bory de St. Vincent 1824) Dujardin '41
Genus CONDYLOSTOMA (KONDYLOSTOMA Bory de St. Vincent 1824) Dujardin '41
Colorless and more or less flexible animals of medium size. The general form is elongate and cylindrical or somewhat smaller anteriorly. The posterior end is broadly rounded, the anterior end somewhat truncate and oblique. The peristome is broad and triangular, the base of the triangle being the entire anterior end of the body. The entire length of the peristome is one-fourth or less of the body length. The mouth is large and placed at the apex of the peristomial triangle and opens into a compar
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Genus STROMBIDIUM Cl. & Lach. '58.
Genus STROMBIDIUM Cl. & Lach. '58.
Small, colorless (except for ingested food) animals with characteristic springing movements. The form is usually constant, but in some cases may be plastic like Astasia ; it is usually globular or conical, the posterior end being more or less pointed, the anterior end broadest. The latter is surrounded by a complete circle of the adoral zone, the oral end of which passes into a peristomial depression which extends deep into the middle of the body. The mouth, with a very small œsophagus, lies at
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Genus TINTINNOPSIS Stein '67.
Genus TINTINNOPSIS Stein '67.
Medium-sized ciliates, inclosed in a chitinous lorica with embedded sand crystals. The form of the house, or lorica, varies greatly. In some cases the mouth opening is wide, giving the lorica a bell form; it may be long and tubular, short and spherical, or variously indented. The animal is attached, as in the closely allied genus Tintinnus , by a peduncle to the bottom of the lorica. The anterior end of the animal is inclosed by two complete circles of cilia; one, the outer, forming the adoral z
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Genus PERITROMUS Stein '62.
Genus PERITROMUS Stein '62.
The body is flat, colorless or tinged with yellow, and contractile. It is elliptical in outline, with broadly rounded ends; in some cases the left edge is slightly incurved, the right edge convex. The ventral surface is flat, the dorsal surface is arched in the middle region of the body. The edges being flat are somewhat more transparent than the remainder of the body. The ventral surface is striated by longitudinal straight or slightly curved lines, the dorsal surface is smooth and without cili
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Genus EPICLINTES Stein '62.
Genus EPICLINTES Stein '62.
Very active, contractile, colorless forms of rather small size. In the fully expanded condition the body is oval and long, with its greatest width in the center or at the front half of the body. The posterior end is always drawn out into a relatively long tail, which is extremely elastic. The peristome is short and stretches around the front end of the animal. In the frontal region are from one to three rows of cirri. The ventral surface is covered with longitudinal rows of cilia, the number of
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Genus AMPHISIA Sterki '78.
Genus AMPHISIA Sterki '78.
The body is plastic and soft, colorless or slightly tinged with yellow or red. In form it is oval or elongate, the posterior end is rounded and slightly reduced in diameter, but does not form a distinct tail. The anterior end is also rounded and similarly reduced in width. There are two rows of marginal cirri ( Randcirren ), which may be placed some distance from the edge, and two or three rows of ventral cirri between them. There are from 3 to 5 frontal cirri of larger size than those of the ve
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Genus EUPLOTES (Ehr. 1831) Stein '59.
Genus EUPLOTES (Ehr. 1831) Stein '59.
Small to medium-sized forms. Rigid in form, colorless, or green by chlorophyl. They are quite flat on the ventral surface but decidedly arched dorsally, and the contour is usually oval. The anterior end is broadly rounded to truncate; the posterior end is similarly rounded, or may be somewhat pointed. The mouth is placed centrally or near the left margin, and from it the right edge of the peristome forms a curved line to the left, which bends forward, thus making the greater part of the left edg
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Genus DIOPHRYS Dujardin '41.
Genus DIOPHRYS Dujardin '41.
Medium size, colorless to yellow, rigid in form. The body contour is oval, the anterior end being rounded or slightly reduced, the posterior end usually cut in on the right side. The peristome is broad but less extensive than in Euplotes , and may extend beyond the middle of the body. Its right edge is convex toward the right side, extends forward and does not turn again to the right. The anterior ventral surface has 7 to 8 scattered cirri and just behind the mouth is a transverse row of large a
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Genus URONYCHIA Stein '52.
Genus URONYCHIA Stein '52.
Medium-sized colorless ciliates of usually constant body form. The body is somewhat short and oval in outline. The anterior end is broadly truncate, the posterior end rounded or slightly pointed. The ventral and dorsal surfaces are considerably arched and the latter usually has a number of rows of longitudinal stripes. The open peristome is broad and reaches back to the middle of the ventral surface and beyond. According to Stein, the two edges can approach each other, thus opening and closing t
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Genus ASPIDISCA Ehr. 1830.
Genus ASPIDISCA Ehr. 1830.
Small, colorless, and rigid forms, with nearly circular to oval contour. The left side is usually straight, or at least but slightly convex. The right side is much more convex, and the right margin is considerably thickened. The ventral side is flat, the dorsal surface convex, with from one to several longitudinal ridges which run more or less parallel with the right edge. The peristome is limited to the left edge, where it forms a small depression which may or may not reach the anterior border,
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Genus LICHNOPHORA Claparède '67.
Genus LICHNOPHORA Claparède '67.
Small or medium-sized colorless animals, extremely elastic and flexible. The anterior part, bearing the adoral zone, is round or oval in ventral view, and has a flat ventral and a highly arched dorsal surface. The posterior end of the animal is reduced to a stalk-like structure which is broadened at the extremity to form a sucking disk. The surface of this disk and the surface of the peristome may be brought into the same plane by the characteristic bending of the stalk portion. A ciliated girdl
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Genus VORTICELLA (Linnæus 1767) Ehr. '38
Genus VORTICELLA (Linnæus 1767) Ehr. '38
Medium-sized ciliates of general bell-like form. They may be colorless, or yellow and green through the presence of Zoochlorella. When not contracted, the peristome end is widespread, rarely narrowed. The adoral zone and peristome agree with the details given in the family characteristics. The chief character is the attachment of the posterior end by means of a single, longer or shorter, stalk, which contains a highly contractile thread easily distinguished in the living animal. Another characte
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Genus ZOOTHAMNIUM (Bory de St. Vincent 1824) Stein '38, '54.
Genus ZOOTHAMNIUM (Bory de St. Vincent 1824) Stein '38, '54.
Colorless and highly contractile forms growing in small or large colonies. The form and structure of the individuals is not different from Vorticella . The colonies are usually richly branched upon the dichotomous plan and the entire colony is contractile. The main character is that with each division of the individual the stalk also divides, each daughter cell getting one-half of the parent stem. The stems therefore remain in communication, so that a simultaneous contraction results, and the co
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Genus COTHURNIA (Ehr. '31) Clap. & Lach. '58.
Genus COTHURNIA (Ehr. '31) Clap. & Lach. '58.
Colorless forms of medium size-in some cases they may be green by Zoochlorella. The general structure is similar to that of Vorticella , but the individuals are elongate and occupy houses. The macronucleus is invariably long and band-form. The distinguishing character is the colorless or brownish lorica of quite variable form but always attached. These houses may be finger-formed, with widened center, or widened mouth, or constricted mouth, and the like. Ring-formed swellings are frequently deve
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Genus PODOPHRYA Ehr. '33.
Genus PODOPHRYA Ehr. '33.
The body is globular, with tentacles radiating in all directions. The tentacles may be very short or very long. The stalk also is either short or long, and some species form stalks but rarely ( P. libera ). The macronucleus is centrally placed and globular to ovoid in form. The contractile vacuole is usually single. Reproduction takes place by division; the distal half developing cilia and becoming a swarm-spore. Fresh and salt water. Podophrya gracilis , n. sp. Fig. 65. Of all the Podophrya tha
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Genus EPHELOTA Str. Wright '78.
Genus EPHELOTA Str. Wright '78.
Small to medium-sized and large forms; colorless to brown. The body is globular or oval or wedge-shape, sometimes quadrangular. The stalk is variable, sometimes 1 mm. in length. The diameter of the stalk increases from the point of attachment to the body of the animal; it is usually striated either longitudinally or transversely, or both. The tentacles are of two kinds and are usually confined to the anterior half of the body. Some are long and sharp-pointed and adapted for piercing; others are
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Genus ACINETA Ehr. '33, Bütschli '88.
Genus ACINETA Ehr. '33, Bütschli '88.
Small to medium-sized forms. The distinguishing feature is that the stalk is swollen at the distal extremity to form a cup or basin in which the animal rests. The cup may be developed until the body is nearly inclosed. The macronucleus is spherical or band form. The contractile vacuole is usually single. Budding, so far as known, is endogenous. Fresh and salt water. Acineta divisa Fraipont '79. Fig. 67. This extremely graceful form is common on Bryozoa at Woods Hole. The cup is shaped like a win
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Genus TRICHOPHRYA Clap. & Lach. '58.
Genus TRICHOPHRYA Clap. & Lach. '58.
Small forms to medium size; no cups or stalks. The body is spherical to elongate, usually, however, more or less irregularly lobed and changeable. The tentacles are in fascicles which are usually borne upon lobed or swollen places. The body is always more or less spread out. Contractile vacuoles variable. The macronucleus is spherical, elongate, band-formed or horseshoe-shaped. Reproduction takes place by endogenous budding, and the swarm spores are flat or lenticular with a distinct ciliary gir
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LIST OF REFERENCES.
LIST OF REFERENCES.
AUERBACH, L. '54. Ueber Encystierung von Oxytricha pellionella. Zeit. wiss. Zool., V, 1854. –––– '55. Ueber die Einzelligkeit der Amoeben. Zeit. wiss. Zool., VII, 1855. BALBIANI E. G. '61. Recherches sur les phénomènes sexuelles des Infusoires. Jour. de la physiol:, IV, 1861. –––– '85. Sur un Infusoire parasite du sang de l'Aselle aquatique. Rec. zool. Suisse, II, 1885. BERGH, R. S. '79. Tiarina fusus Cl. & Lach. Vid. Med. f. d. Nat. Foren. Kjobenhavn. –––– '82. Der Organismus der Ciliof
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