The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . ite ao asto form a germinating spore f la the lowertwo cells spiral filaments are seen. few in number, which open into the apex of the femaleorgan, and discharge their- antherozoids. The result isthe formation of ceUular tissue round the ascogonium,forming what is termed a perithecium, and within theascogonium large jells {atci) are produced, in which spores. IN CRYPTOQAMS.] BOTANY 159 or sporidia are subsequently developed. In Lichens nosexual organs have as yet been clearly demonstrated. Amongst Fungi an
The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . ite ao asto form a germinating spore f la the lowertwo cells spiral filaments are seen. few in number, which open into the apex of the femaleorgan, and discharge their- antherozoids. The result isthe formation of ceUular tissue round the ascogonium,forming what is termed a perithecium, and within theascogonium large jells {atci) are produced, in which spores. IN CRYPTOQAMS.] BOTANY 159 or sporidia are subsequently developed. In Lichens nosexual organs have as yet been clearly demonstrated. Amongst Fungi and Lichens there are certain bodiesto be noted, which may be connected with sexual repro-•duction, but tho function of which is at present in the margin of the thallus in Lichens andon various parts of the plant in Fungi, certain hollow urn-shaped bodies are found, which have been termed spervia-yones (conceptacles) (fig. 334). These are usually closedall but a small opening at the apex. From thoir base risepeg-shaped projections or steru/mata (fig. 335), bearing at. Fig. 334. Fig. 335. Flo. 334.—Two spermagonea on thalll of Llchen§. Fio. 335.—Sterigmuta a and epermatia b of Ciadonia Jinibltata. their summit elongated, sometimes curved, bodies, termedipermatia, which, when mature, are discharged throughthe apex of the spermagone. These are by some con-sidered the analogues of the antherozoids in otherCryptogams. There are also found other conceptacles, towhich the name of pycnidia or pycnides is given. Thesecontain large spores, which have been termed stylospoia(fig. 336), but their homology is at present unknown. Another process of reproduction is seen amongst Crypto-gams. This is termed conjugation (fig. 333). It differsfroin the process of fertilization just described in that itconsists of a union of the contents of two similar cells, whilstfertilization essehtiaUy consists in the mutual influence ofdissimilar cells. It is well seen in many Algse, such
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