The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . s the femaleorgans, or they may beseparate and surround-ed by a perigone ; but thev are always formed A speciesof LlverwortCi/arcAan^fapofirtnwrAa) ?I - J with its green thallus (, bcaiing a cup-Uko upon the leaf-bearing body y, in which minute cells or free buds are ovio citlipr tprminnl or »«^° ?^^ » stalked receptacle i, r. In the axis, eitner terminal or j^tgtance of the dlsk-llke receptacle r CcUs lateral. In Ferns and are produced conUinlng phytozoa. These aro t^ . .1 considered antheridia. Equisetum
The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . s the femaleorgans, or they may beseparate and surround-ed by a perigone ; but thev are always formed A speciesof LlverwortCi/arcAan^fapofirtnwrAa) ?I - J with its green thallus (, bcaiing a cup-Uko upon the leaf-bearing body y, in which minute cells or free buds are ovio citlipr tprminnl or »«^° ?^^ » stalked receptacle i, r. In the axis, eitner terminal or j^tgtance of the dlsk-llke receptacle r CcUs lateral. In Ferns and are produced conUinlng phytozoa. These aro t^ . .1 considered antheridia. Equisetum they are produced on the surface—usually the lower surface—of a cellular flattened expansion, termed a prothallus (figs. 245, 250), in close proximity to the female organs. In Characea; they always arise from the termination of one of the whorled leaflets. In some i^ycopodiacese no antheridia have as yet beenfound; but in Selaginella, Isoetes, and in the Rhizo-carpeae, hollow sacs, termed microsporangia (figs. 246,248), are produced in the axil of certain leaves of the. Fig. 243. PISTIL.] B 0 T A 2^ Y 141 plant, in which small cells, microspores (fig. 2-19;, arefuund, each consisting of an outer covering or exospore,and an inner or cnJosporc. Within microsporeb (thpmanner vaV)ing iu diflcrcnt genera) smaller celk arc formed,.which are the mother-cells of the antherozoids. lu this
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