. A practical course in botany, with especial reference to its bearings on agriculture, economics, and sanitation. Botany. CRYPTOGAMS 343. Fig. 485. — Fruiting recep- tacle of a moss (Phascum cus- pidatum), bearing both anther- idia, an, and archegonia, ar, at the bifurcated apex; b, leaves ; p, paraphyses. axes, or of lateral branches (Figs. 485, 486), but as a rule only one archegonium is fertilized, so the mature sporo- gonia are solitary. The plants may be either dioecious or monoecious, as in Fig. 485; and in w ^f the latter case, the reproductive organs may be borne on the same, or on di
. A practical course in botany, with especial reference to its bearings on agriculture, economics, and sanitation. Botany. CRYPTOGAMS 343. Fig. 485. — Fruiting recep- tacle of a moss (Phascum cus- pidatum), bearing both anther- idia, an, and archegonia, ar, at the bifurcated apex; b, leaves ; p, paraphyses. axes, or of lateral branches (Figs. 485, 486), but as a rule only one archegonium is fertilized, so the mature sporo- gonia are solitary. The plants may be either dioecious or monoecious, as in Fig. 485; and in w ^f the latter case, the reproductive organs may be borne on the same, or on different, receptacles. The antheridia and the archegonia are both mixed with club- shaped hairs called paraphyses (Fig. 485). 399. The sporophyte. — An examination of the fruiting capsule of any of the true mosses will show that it consists of a long footstalk, the seta, s, Fig. 486, bearing a capsule, or ripened sporogonium, /, which is at first surmounted by a cap or hood, known as the calyptra, c. The hood repre- sents the excessively developed and often highly specialized wall of the archegonium. It falls away at maturity, and the spores are discharged through an opening made by the removal of the operculum, or lid, d. The ing stem of a moss spores and the capsule are both developed (^°^™^fm, com- r . , . . mune) with ripe cap- from the fertilized egg (oospore), within the suies: s,seta,orfoot- archegonium, in much the same manner as in ^dyptra "^capsule the liverworts, and together constitute the after the calyptra has , , t ,. T, fallen away; d, oper- sporophyte, or asexual generation. It never Cuium, or lid. leads a completely independent existence, but remains a partial parasite on the mother plant, though the lower part of the young sporogonium is usually provided with stomata. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not p
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