. Physiological botany; I. Outlines of the histology of phænogamous plants. II. Vegetable physiology. Plant physiology; Plant anatomy. EEPEODtrCTION IN CRYPTOGAMS. 441 of flowcrless plants. Comparative investigations liave, however, siiovvn that such gradations do exist, and that the chain of exist- fevtilization is shown in the figure. Of the more complicated cases this is not the place to speak ; their treatment, as well as that of all the simpler forms, may be looked for in Volume III. Specimens for this demonstration of the different stages of reproduction are to be procured at different
. Physiological botany; I. Outlines of the histology of phænogamous plants. II. Vegetable physiology. Plant physiology; Plant anatomy. EEPEODtrCTION IN CRYPTOGAMS. 441 of flowcrless plants. Comparative investigations liave, however, siiovvn that such gradations do exist, and that the chain of exist- fevtilization is shown in the figure. Of the more complicated cases this is not the place to speak ; their treatment, as well as that of all the simpler forms, may be looked for in Volume III. Specimens for this demonstration of the different stages of reproduction are to be procured at different seasons. As will be seen from the figure, most of the features are so nearly supei-ficial as to need no particular sections for their exhibition. / (5) True mosses and their allies are characterized by the posses,sion of au archegonium or flask-shaped body containing a central cell in which is the oosphere. The oosphere fertilized by immediate contact with antherozoids â which are formed in antheridia; as a result of the fertilization, there is produced a spore-case filled with spores. In the examination of the fructification of a moss, the plant must be taken at an early stage, and search must be made for the sexual organs by remo\ al of the flower-like cluster of leaves at the summit of the minute 2. stalk. If the removal is success- fully performed, and the plant is in the right condition, a group of threads like those shown in the figure will be plainly seen. Among these are to be foTmd some flask-like bodies, the arche- gonia, and either on the same receptacle or on another plant of the same species the male organs, one of which, greatly magnified, is shown in Fig. 212. Under a very high power the escaping antherozoids can be seen. When fertilization has taken place, the archegoniuui goes on in its development, be- coming, after many intermediate steps, the capsule or "fruit" of the moss, covered by a sort of hood or cap, and tightly closed at its mouth by
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectplantanatomy, bookyea
