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A Handbook Of Systematic Botany

Eugenius Warming

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A HANDBOOK OF SYSTEMATIC BOTANY

A HANDBOOK OF SYSTEMATIC BOTANY

BY DR. E. WARMING Professor of Botany in the University of Copenhagen With a Revision of the Fungi by DR. E. KNOBLAUCH, Karlsruhe Translated and Edited by M. C. POTTER, M.A. F.L.S. Professor of Botany in the University of Durham College of Science, Newcastle-upon-Tyne Author of “An Elementary Text-book of Agricultural Botany” WITH 610 ILLUSTRATIONS London SWAN SONNENSCHEIN &amp; CO NEW YORK: MACMILLAN &amp; CO 1895 Butler &amp; Tanner, The Selwood Printing Works, Frome, and London...

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PREFACE.

PREFACE.

The present translation of Dr. E. Warming’s Haandbog i den Systematiske Botanik is taken from the text of the 3rd Danish Edition (1892), and from Dr. Knoblauch’s German Edition (1890), and the book has been further enriched by numerous additional notes which have been kindly sent to me by the author. Dr. Warming’s work has long been recognised as an original and important contribution to Systematic Botanical Literature, and I have only to regret that the pressure of other scientific duties has d

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CORRIGENDA.

CORRIGENDA.

For ä, ö and ü read æ, œ and ue throughout. The following are not officinal in the British Pharmacopœia:—page 316, Dracæna (Dragon’s-blood), Smilax glabra ; p. 321, “Orris-root”; p. 326, species of Curcuma , Alpinia officinarum ; p. 333, Orchis -species (“Salep”). On page 296 , par. 4, only Pearl Barley is offic. in the Brit. Phar....

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CLASSIFICATION OF THE VEGETABLE KINGDOM.

CLASSIFICATION OF THE VEGETABLE KINGDOM.

The Vegetable Kingdom is arranged in 5 Divisions. Division I.— Thallophyta , Stemless Plants , or those which are composed of a “thallus,” i.e. organs of nourishment which are not differentiated into root (in the sense in which this term is used among the higher plants), stem, or leaf. Vascular bundles are wanting. Conjugation and fertilisation in various ways; among most of the Fungi only vegetative multiplication. In contradistinction to the Thallophytes all other plants are called “Stem-plant

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DIVISION I. THALLOPHYTA.

DIVISION I. THALLOPHYTA.

The thallus in the simplest forms is unicellular; in the majority, however, it is built up of many cells, which in a few instances are exactly similar; but generally there is a division of labour, so that certain cells undertake certain functions and are constructed accordingly, while others have different work and corresponding structure. Vessels or similar high anatomical structures are seldom formed, and the markings on the cell-wall are with few exceptions very simple. The Myxomycetes occupy

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Sub-Division I.—MYXOMYCETES, SLIME-FUNGI.

Sub-Division I.—MYXOMYCETES, SLIME-FUNGI.

The Slime-Fungi occupy quite an isolated position in the Vegetable Kingdom, and are perhaps the most nearly related to the group of Rhizopods in the Animal Kingdom. They live in and on organic remains, especially rotten wood or leaves, etc., on the surface of which their sporangia may be found. They are organisms without chlorophyll, and in their vegetative condition are masses of protoplasm without cell-wall ( plasmodia ). They multiply by means of spores , which in the true Slime-Fungi [3] are

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Class 1. Syngeneticæ.

Class 1. Syngeneticæ.

The individuals are uni- or multicellular, free-swimming or motionless. The cells (which in the multicellular forms are loosely connected together, often only by mucilaginous envelopes) are naked or surrounded by a mucilaginous cell-wall, in which silica is never embedded. They contain one cell-nucleus, one or more pulsating vacuoles, and one to two band- or plate-like chromatophores with a brown or yellow colour, and sometimes a pyrenoid. Reproduction takes place by vegetative division, or asex

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Class 2. Dinoflagellata.

Class 2. Dinoflagellata.

The individuals are of a very variable form, but always unicellular, and floating about in free condition. The cell is dorsiventral , bilateral , asymmetric and generally surrounded by a colourless membrane, which has no silica embedded in it, but is formed of a substance allied to cellulose . The membrane, which externally is provided with pores and raised borders, easily breaks up into irregularly-shaped pieces. In the forms which have longitudinal and cross furrows, two cilia are fixed where

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Class 3. Diatomeæ.

Class 3. Diatomeæ.

The individuals—each known as a frustule —assume very various forms and may be unicellular or multicellular, but present no differentiation; many similar cells may be connected in chains, embedded in mucilaginous masses, or attached to mucilaginous stalks. The cells are bilateral or centric, often asymmetrical, slightly dorsiventral and have no cilia; those living in the free condition have the power of sliding upon a firm substratum. The cell contains 1 cell-nucleus and 1–2 plate-shaped or seve

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Class 4. Schizophyta, Fission-Algæ.

Class 4. Schizophyta, Fission-Algæ.

The individuals are 1—many celled; the thallus consists in many of a single cell, in others of chains of cells, the cells dividing in only one definite direction (Figs. 18 , 21 ). In certain Fission-Algæ the cell-chain branches (Fig. 30 ) and a difference between the anterior and the posterior ends of the chain is marked; in some, the cells may be united into the form of flat plates by the cell-division taking place in two directions; and in others into somewhat cubical masses, or rounded lumps

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Class 5. Conjugatæ.

Class 5. Conjugatæ.

The Algæ belonging to this class have chlorophyll, and pyrenoids round which starch is formed. The cells divide only in one direction, they live solitarily, or united to form filaments which generally float freely (seldom attached). Swarm-cells are wanting. The fertilisation is isogamous (conjugation) and takes place by means of aplanogametes. The zygote, after a period of rest, produces, immediately on germination, one or more new vegetative individuals; sometimes akinetes or aplanospores are f

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Class 6. Chlorophyceæ (Green Algæ).

Class 6. Chlorophyceæ (Green Algæ).

These Algæ are coloured green by chlorophyll, seldom in combination with other colouring matter, and then especially with red. The product of assimilation is frequently starch, which generally accumulates round certain specially formed portions of protoplasm termed pyrenoids. The thallus is uni- or multicellular; in the higher forms (certain Siphoneæ) the organs of vegetation attain differentiation into stem and leaf. The asexual reproduction takes place in various ways; the sexual reproduction

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Class 7. Characeæ.

Class 7. Characeæ.

The thallus has a stem with nodes and internodes; and whorls of leaves, on which may be developed the antheridia and oogonia, are borne at the nodes. Vegetative reproduction by bulbils and accessory shoots. Zoospores are wanting. The antheridia are spherical, and contain a number of filaments in which the spirally coiled spermatozoids, each with two cilia, are formed. The oogonium is situated terminally, and is at first naked, but becomes later on surrounded by an investment, and forms after fer

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Class 8. Phæophyceæ (Olive-Brown Seaweeds).

Class 8. Phæophyceæ (Olive-Brown Seaweeds).

The Phæophyceæ are Algæ, with chromatophores in which the chlorophyll is masked by a brown colour (phycophæin). The product of assimilation is a carbohydrate (fucosan), never true starch . In the highest forms ( Fucaceæ ), the thallus presents differentiation into stem, leaf, and root-like structures. The asexual reproduction takes place by means of zoospores. The sexual reproduction is effected by the coalescence of motile gametes, or by oogamous fertilisation. The swarm-cells are monosymmetric

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Class 9. Dictyotales.

Class 9. Dictyotales.

The plants in this class are multicellular, and brown, with apical growth, new cells being derived either from a flat apical cell, or from a border of apical cells. The thallus is flat, leaf- or strap-shaped, attached by haptera, which are either found only at the base, or on the whole of the lower expansion of the thallus. The cells are differentiated into the following systems of tissues: an external, small-celled layer of assimilating cells, generally one cell in thickness, and an internal, l

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Class 10. Rhodophyceæ (Red Seaweeds).

Class 10. Rhodophyceæ (Red Seaweeds).

The plants comprised in this class are multicellular; they are simple or branched filaments, or expansions consisting of 1 to several layers of cells; the thallus may be differentiated (as in many Florideæ ), to resemble stem, root, and leaf. The cells contain a distinctly differentiated nucleus (sometimes several), and distinct chromatophores, coloured by rhodophyll. The chlorophyll of the chromatophores is generally masked by a red colouring matter (phycoerythrin), which may be extracted in co

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Class 1. Phycomycetes (Algal-Fungi).[12]

Class 1. Phycomycetes (Algal-Fungi).[12]

This group resembles Vaucheria and the other Siphoneæ among the Algæ. Organs of Nutrition. The mycelium is formed of a single cell, often thread-like and abundantly branched (Fig. 78 ). Vegetative propagation by chlamydospores and oidia. Asexual reproduction by endospores (sometimes swarmspores ) and conidia. Sexual reproduction by conjugation of two hyphæ as in the Conjugatæ, or by fertilisation of an egg-cell in an oogonium. On this account the class of the Phycomycetes is divided into two sub

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Sub-Class I. Zygomycetes.

Sub-Class I. Zygomycetes.

Sexual reproduction takes place by zygospores, which function as resting-spores, and arise in consequence of conjugation (Fig. 81 ); in the majority of species these are rarely found, and only under special conditions. The most common method of reproduction is by endospores, by acrogenous conidia, by chlamydospores, or by oidia. Swarmspores are wanting. Parasites and saprophytes (order 6 and 7). The zygospores are generally produced when the formation of sporangia has ceased; e.g. by the suppres

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Sub-Class 2. Oomycetes.

Sub-Class 2. Oomycetes.

Sexual reproduction is oogamous with the formation of brown, thick-walled oospores which germinate after a period of rest. Asexual reproduction by conidia and swarmspores . Parasites, seldom saprophytes. The oospores are large spores which are formed from the egg-cell (oosphere) of the oogonium (oosporangium, Fig. 89 , 95 ). A branch of the mycelium attaches itself to the oogonium and forms at its apex the so-called “ antheridium ” (pollinodium [13] ): this sends one or more slender prolongation

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Class 2. Mesomycetes.

Class 2. Mesomycetes.

The Mesomycetes are intermediate forms between the Phycomycetes and the Higher Fungi. In the vegetative organs, and in the multicellular hyphæ, they resemble the Higher Fungi; the methods of reproduction, however, show the characters of the Phycomycetes, namely sporangia and conidiophores of varying size and with varying number of spores; definite and typically formed asci and basidia are not present. Sexual reproduction is wanting. The Hemiasci are transitional between the Phycomycetes and the

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Sub-Class 1. Hemiasci.

Sub-Class 1. Hemiasci.

The Hemiasci are Fungi with sporangia which, although resembling asci , yet have not , however, a definite form and a definite number of spores . Besides endospores, conidia, chlamydospores and oidia are found. Order 1. Ascoideaceæ. Ascoidea rubescens forms irregular, reddish-brown masses in the sap issuing from felled Beeches. It has free sporangia , which resemble asci in their structure, in the development and ejection, and in the definite shape and size of the spores. The formation of the sp

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Sub-Class 2. Hemibasidii, Brand-Fungi.

Sub-Class 2. Hemibasidii, Brand-Fungi.

The Brand-Fungi (also known as Ustilagineæ ) are Fungi with basidia-like conidiophores , which, however, have not yet advanced to a definite form or number of conidia. They are true parasites, whose mycelium spreads itself in the intercellular spaces of Flowering plants. The mycelium is colourless, quickly perishable, has transverse walls at some distance from each other (Fig. 96 ), and sends out haustoria into the cells of the host-plant. Fig. 96. — Entyloma ranunculi. 1. Cross section of a por

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Class 3. Mycomycetes, Higher Fungi.

Class 3. Mycomycetes, Higher Fungi.

The Mycomycetes are not entirely aquatic in habit; they have hyphæ with transverse walls , but no sexual reproductive organs . The asexual reproduction takes place in very different ways; by endospores (in asci), conidia, basidiospores, chlamydospores, and oidia. Swarmspores are never found. Two chief methods of reproduction may be distinguished, and hence the class may be divided into two large sub-classes:—the Ascomycetes (with asci), and the Basidiomycetes (with basidia)....

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Sub-Class 1. Ascomycetes.

Sub-Class 1. Ascomycetes.

The main characteristic which distinguishes the Ascomycetes is the ascus ; a name given to a sporangium of a definite shape and size, and containing a definite number of spores. The shape is generally club-like or spherical, the number of spores 8 (in some 2, 4, 16 or more), see Figs. 103 , 105 , 108 , 110 , 113 , 116 , 120 , 121 , 123 , 129 . In the lowest forms, the Exoasci , the ascus springs directly from the mycelium without the formation of a fruit-body ( i.e. ascocarp). In the higher form

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Sub-Class 2. Basidiomycetes.

Sub-Class 2. Basidiomycetes.

This sub-class embraces the most highly developed Fungi, with large “fruit-bodies,” which in ordinary language we shortly term Funguses, Toadstools, or Mushrooms. They have no sporangia, but reproduce only by means of basidiospores, conidia, chlamydospores and oidia. The chief characteristic of this sub-class is the basidium (Fig. 145 ), i.e. the conidiophore, which has a distinctive form, and bears a definite number (generally 4) of characteristically shaped conidia (basidiospores, Fig. 145 c ,

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Class 1. Hepaticæ (Liverworts).

Class 1. Hepaticæ (Liverworts).

The protonema is only slightly developed. The remaining part of the vegetative body is either a prostrate, often dichotomously-branched thallus, pressed to the substratum (thalloid Liverworts), with or without scales on the under side (Figs. 194 , 197 ); or a thin, prostrate, creeping stem, with distinctly-developed leaves, which are borne in two or three rows (Figs. 195 , 198 ), viz., two on the upper and, in most cases, one on the under side. The leaves situated on the ventral side (amphigastr

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Class 2. Musci frondosi or veri (True Mosses).

Class 2. Musci frondosi or veri (True Mosses).

In this class the protonema is well developed, and resembles a branched filamentous Alga, from which it can be easily distinguished by its oblique septa (in Sphagnum it is a cellular expansion). The Moss-plant, which is developed directly from the protonema, generally has an erect, thick, cylindrical stem similarly constructed on all sides. The leaves are arranged spirally, the most frequent divergence being 2/5 or 3/8 (Fig. 200 A ). A midrib is often present and also marginal veins formed by lo

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Class 1. Filicinæ (Ferns).

Class 1. Filicinæ (Ferns).

The characteristics of this class have already been given on page 204 . The class is divided into two sub-classes:— 1. The True Ferns , Filices , have one kind of spore which generally developes monœcious prothallia, relatively large and green. The sporangia are most frequently situated in groups ( sori ), which are often covered but not enclosed by an indusium . 2. Water Ferns , Hydropteridæ , have microsporangia with many (4 × 16) microspores, and macrosporangia, each with one macrospore . The

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Sub-Class 1. Filices (the True Ferns).

Sub-Class 1. Filices (the True Ferns).

Of the eight orders (with about 4,000 species) comprised in this sub-class, the Polypodiaceæ is the largest (having about 2,800 species) and the most familiar; for this reason it will be taken as typical. The sexual generation. When the spore germinates, the external covering (exospore) is ruptured, as in the Mosses. The internal cell-wall (endospore) grows out as a filament, which soon divides and gives rise to the prothallium, a flat, cellular expansion resembling the thallus of a Liverwort. I

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Sub-Class 2. Hydropterideæ (formerly Rhizocarpeæ), Water Ferns.

Sub-Class 2. Hydropterideæ (formerly Rhizocarpeæ), Water Ferns.

The following further characteristics must be added to those given on page 205:— Fig. 214. — Salvinia natans : A microsporangium with germinating microspores and protruding prothallia ( s ); B a prothallium with the bicellular antheridium ( s ) growing out of the microsporangium; C the two cells of the antheridium have opened by transverse clefts; beneath is seen the microspores enclosed by the hardened mucilage; D spermatozoids still enclosed in the mother-cells. Fig. 215. — Salvinia natans. A

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Class 2. Equisetinæ (Horsetails.)

Class 2. Equisetinæ (Horsetails.)

The characteristics of this class have been described on page 204 . It is divided into two sub-classes:— 1. The isosporous Equisetinæ. To this sub-class belong, with certainty, only the Equisetaceæ now existent, which are represented by only one genus, Equisetum . 2. The heterosporous Equisetinæ. Forms which are now extinct....

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Sub-Class 1. Isosporous Equisetinæ.

Sub-Class 1. Isosporous Equisetinæ.

Order. Equisetaceæ (Horsetails). Fig. 222. — Equisetum arvense. The prothallium highly magnified. A Male; s, s antheridia. B Portion of a female, cut through vertically; œ œ archegonia, the central one is fertilised; h h root-hairs. Fig. 223. — Equisetum maximum. Spermatozoids: a shows them still enveloped by the mother-cell. The sexual generation. The prothallium is green and leaf-like, as in the majority of Ferns, but irregularly branched and curled. It is often unisexual. The male prothallia

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Sub-Class 2. Heterosporous Equisetinæ.

Sub-Class 2. Heterosporous Equisetinæ.

The two orders which come under this head are united by the characteristics, that the verticillate leaves are not united into sheaths (Fig. 226 ), and that between each whorl of fertile leaves there is also a whorl of barren ones. The fertile whorls in Annulariæ are situated about midway between the barren ones (Fig. 227 ), but in Asterophylliteæ they occur immediately above a barren whorl (Fig. 228 ) and contain only half as many members as the latter. The lower whorls bear macrosporangia with

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Class 3. Lycopodinæ (Club-Mosses).

Class 3. Lycopodinæ (Club-Mosses).

The characteristics of this class have been given on page 205 . It consists of two sub-classes, one embracing isosporous, the other heterosporous forms....

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Sub-Class 1. Lycopodieæ (Isosporous Lycopodinæ).

Sub-Class 1. Lycopodieæ (Isosporous Lycopodinæ).

One kind of spore. Prothallium large, partly green. Leaves without ligule. Fig. 229. — Lycopodium annotinum : A embryo (nat. size), with prothallium ( pr ), one embryo is broken off; B the prothallium (slightly magnified); C section through the prothallium and embryo in the direction a-b of A , and vertically in the plane of the paper. Fig. 230. — Lycopodium clavatum : portion of a stem, bearing cones ( a ); s a spore; h sporangium in the axil of a leaf, s . Order 1. Lycopodiaceæ. The PROTHALLIU

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Sub-Class 2. Selaginelleæ (Heterosporous Lycopodinæ).

Sub-Class 2. Selaginelleæ (Heterosporous Lycopodinæ).

Micro-and macrospores. The prothallia are very much reduced, especially the male; the female does not leave the spore. The leaves are ligulate. Fig. 233. —Germination of the microspores of Selaginella : A the spore rendered transparent, seen from above. In the interior is seen the prothallium ( f ), and the first divisions of the antheridium ( a , b , c , d ); in B the spore-wall is removed and all the spermatozoid-mother-cells formed; in C , the microspore has opened and the spermatozoids and t

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The Transition from the Cryptogams to the Phanerogams.

The Transition from the Cryptogams to the Phanerogams.

All the plants considered in the preceding chapters are included in the term Cryptogams ; all in the following chapters under the head of Phanerogams (see page 3 ). Hofmeister’s pioneer works (1851, Vergleichende Untersuchungen der höheren Kryptogamen , etc.) and the numerous researches published later by other investigators, have closed the gap which was formerly thought to exist between these plants; so that we now, in the series: Bryophyta—Pteridophyta—Gymnospermæ—Angiospermæ see the expressi

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Class 1. Cycadeæ.

Class 1. Cycadeæ.

The stem is very rarely ramified . The leaves are large , pinnate , and arranged spirally. The flowers are diœcious, without perianth . Fig. 256. — Cycas circinalis (female plant). The carpels are seen hanging from the top of the stem. Three leaves with the leaflets still rolled up project almost vertically into the air, from the centre of the crown. There is only one order, the Cycadaceæ .—In habit they resemble the Ferns, especially the Tree-Ferns (compare Figs. 207 and 256 ). The stem is tube

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Class 2. Coniferæ (Pine-trees).

Class 2. Coniferæ (Pine-trees).

The stem branches freely . The leaves are entire , relatively small, linear or reduced to scales. The flowers are without perianth. The ovules naked. It is seldom that the female flower is reduced to only one carpel. Whilst the Cycadeæ principally resemble the Ferns, the Conifers partly resemble the Lycopods, and partly the Equisetums—the former especially in the needle- or scale-like , leathery, simple, and often perennial leaves (“evergreen plants”), which never possess stipules (Figs. 263 , 2

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Class III. Gneteæ.

Class III. Gneteæ.

This class, independent of extinct forms, comprises the most highly developed of the Gymnosperms, partly from the circumstance that a perianth of 2–4 members encloses the terminally placed ovule , which is provided with one, or (in Gnetum ) two, integuments, and partly owing to the fact that the wood has true vessels. There is only one order. Fig. 275. — Welwitschia mirabilis (considerably reduced). The horizontal lines indicate the surface of the soil. Order. Gnetaceæ. The three known genera di

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Class 1. Monocotyledones.

Class 1. Monocotyledones.

The embryo has only one cotyledon; the leaves are as a rule scattered, with parallel venation; the vascular bundles of the stem are closed, there is no increase of thickness. The flower is typically constructed of five 3-merous whorls, placed alternately. The embryo is generally small in proportion to the abundant endosperm (exceptions, see Helobieæ ), and its single cotyledon is often sheath-like, and very large. On the germination of the seed either the entire cotyledon, or its apex only, most

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Class II. Dicotyledones.

Class II. Dicotyledones.

In this class THE EMBRYO has 2 seed-leaves, a rule from which there are few exceptions ( e.g. Ficaria , Cyclamen , Pinguicula , certain species of Corydalis , with only 1; and a few, mostly parasitic forms, e.g. Monotropa , Orobanche , Pyrola , entirely without cotyledons). On germination the cotyledons nearly always raise themselves above the ground as green, assimilating leaves and are then termed aerial or epigean, in contradistinction to the underground or hypogean which are always buried. T

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Sub-Class 1. Choripetalæ. Petals free.

Sub-Class 1. Choripetalæ. Petals free.

Trees and shrubs, which, in the structure of the vegetative shoot and the catkin-like inflorescences, resemble the Quercifloræ, but the structure of the flower differs so much from them, that the only order brought under this heading— Salicaceæ —well deserves to be separated and to form a family of its own, the nearest relatives of which are still doubtful. As Juglandaceæ and Myricaceæ also deserve to be placed in a special family, the name Amentaceæ ( Catkin-bearers ), hitherto applied to all o

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Sub-Class 2. Sympetalæ.

Sub-Class 2. Sympetalæ.

The characters which separate this from the first Sub-class, the Choripetalæ, have been described on page 336 . They consist in the following: the flower is always verticillate, generally with 5 sepals, 5 petals, 5 stamens, and 2 carpels (in the median plane), the calyx is generally persistent and gamosepalous, the corolla is gamopetalous and united to the stamens, which are therefore adnate to it, the ovules have only one thick integument and a small nucellus. (The exceptions are noted later.)

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A. Pentacyclicæ.

A. Pentacyclicæ.

This family is chiefly composed of shrubs, less frequently of small trees, or perennial herbs; their leaves are undivided, most frequently evergreen, stiff and leathery, and always without stipules. The flowers are ☿ and regular , rarely slightly zygomorphic, most frequently obdiplostemonous, and 4- or 5-merous through all the 5 whorls. The stamens are attached to the receptacle , and as a rule are quite free from the petals, an attachment which is very rare among the Gamopetalæ. They have a sim

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B. Tetracyclicæ.

B. Tetracyclicæ.

The flower is regular, ☿, and hypogynous . The gamopetalous type is present in this family with great uniformity, without suppression or splitting; S5, P5, A5, G2 (3–5). The stamens are all fertile, alternating with the lobes of the corolla. Gynœceum with 2, more seldom 3–5 syncarpous carpels. Style nearly always simple; 2 dorsal stigmas. In each carpel 2–∞ ovules. At the base of the ovary is found a yellowish ring-like nectary (Fig. 552 C), sometimes 5-sinuate or 5-partite.—The leaves are nearl

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b. Tetracyclicæ with epigynous flowers.

b. Tetracyclicæ with epigynous flowers.

The leaves are always opposite or verticillate. The flower is epigynous , ☿, 5-(or 4-) merous, with the usual sympetalous diagram; 2–5 carpels. The inflorescences are frequently dichasial. The sepals are small, reduced to teeth, and become almost entirely suppressed in the higher forms.—The flower is regular in Rubiaceæ and some Caprifoliaceæ , but in other genera of this latter order (especially of Lonicereæ ) it is unsymmetrical. In several genera of the order first mentioned the loculi of the

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APPENDIX ON THE CLASSIFICATION OF PLANTS.

APPENDIX ON THE CLASSIFICATION OF PLANTS.

By M. C. POTTER. The earliest systems of classification were derived from the properties and uses of plants; and it was not until some two centuries ago that any scientific grouping of plants was attempted. Aristotle and Theophrastus had adopted the groups of Trees, Shrubs and Herbs as the chief divisions of the Vegetable Kingdom, a system which persisted and was employed by Tournefort and Ray as late as the end of the 17th century. The arrangement by which these three divisions were separated i

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