. A manual of structural botany; an introductory textbook for students of science and pharmacy. Plant morphology. THE BRYOPHYTA 213 Different sexes are borne on different plants. The female organ consists of a number of simple ovaries (Oogonia) (Fig. 592, c; Fig. 593, og), grouped together in a Conceptacle. Each oogonium contains eight Oospheres. These oospheres are set free and are fertilized by motile Gametes, the Antherozoids, which are produced in conceptacles of another plant. The Lichens.—IMost systematists now regard the Lichens as belonging to the Fungi. They may be defined as Fungi pa
. A manual of structural botany; an introductory textbook for students of science and pharmacy. Plant morphology. THE BRYOPHYTA 213 Different sexes are borne on different plants. The female organ consists of a number of simple ovaries (Oogonia) (Fig. 592, c; Fig. 593, og), grouped together in a Conceptacle. Each oogonium contains eight Oospheres. These oospheres are set free and are fertilized by motile Gametes, the Antherozoids, which are produced in conceptacles of another plant. The Lichens.—IMost systematists now regard the Lichens as belonging to the Fungi. They may be defined as Fungi parasitic on certain Algae. In this form of parasitism each plant supplies some indispen- sable contribution to the other, the relation being therefore called Sym- biosis. The body of the Lichen, more particularly in the larger forms, is made up of the Fungus mycelium (Fig. 595, sh). The thallus may. Fig. 594. General view of several Lichens: A, criistaceous (Graphis); B, a portion of this sameliclien more highly magnified, showing apothecia; C, a erustaceous lichen, Pertusaria; D, a sub-foliaceous thallus of Parmelia with numerous spore-bearing bodies, apothecia. (Sachs.) be large and flat, leathery and leaf-like (foliaceous. Fig. 594, D), or upright and branching (fruticose), or close-clinging to the bark of trees, looking like a colored stain on rocks (erustaceous. Fig. 594,A, C). In most cases the spores are born^ eight together, in little sacs called Asci, which are themselves reproduced in variously colored closed or open Apothecia (Fig. 594, D). The Bryophyta.—In this class the conspicuous generation is the gametophyte which, in the higher divisions (left hand, Fig. 59G), becomes a well-developed plant with stem and leaves. Its male repro- ductive organs are the Antheridia (Fig. 597, a); its female are the Archegonia. The effect of reproduction is the production of an embryo, which immediately germinates while upon the gametophyte, sending its foot down into the tissue
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