Text-book of botany, morphological and physiological . the circumference of this that themother-cells of the spores are formed. Thestructure of the mature capsule, and espe-cially the contrivances for dispersing thespores, are, however, so different in thevarious principal sections of Mosses thatit will be better to consider them moreclosely separately, and the more so because by this means we shall at the sametime arrive at the distinctive characters of the larger natural systematic groups. In the mode of origin of the sporogonium there is, as might be expected,less variety. The oospore is fi
Text-book of botany, morphological and physiological . the circumference of this that themother-cells of the spores are formed. Thestructure of the mature capsule, and espe-cially the contrivances for dispersing thespores, are, however, so different in thevarious principal sections of Mosses thatit will be better to consider them moreclosely separately, and the more so because by this means we shall at the sametime arrive at the distinctive characters of the larger natural systematic groups. In the mode of origin of the sporogonium there is, as might be expected,less variety. The oospore is first of all clothed with a cell-wall, continues to growconsiderably, and is then divided by a (horizontal ? or) slightly inclined asserts that in Bryum argenteum the upper cell (that facing the neckof the archegonium) is again divided once or twice by horizontal septa before thefirst oblique division, while in Phascum, Funaria, Andreaea, and Fissidens, thisoblique septum is formed immediately after the first horizontal one. The apical. Fig. 236.—Ftinaria hygronietrica; A origin of the spo-rogonium ff in the ventral portion b b oi the archego-nium ; (longitudinal section X500) ; B, C different furtherstages of development of the sporogonium y and of thecalyptra c; h neck of the archegonium (x about 4°)- MOSSES. 325 cell now forms two rows of segments by partition-walls inclined alternately, andthese segments are next divided by radial vertical walls, followed by furthernumerous transverse divisions. By this process the young sporogonium growingat its apex is transformed into a multicellular body which is usually fusiform, thelower end not participating in the growth in length. A swelling of this lowerend, such as usually occurs in Hepatic^, takes place also in Sphagnum and Archi-dium. The apex of the sporogonium now becomes inactive, and beneath it thecapsule is formed from a spherical, ovoid, cylindrical, or frequently unsymmetricalswelling which originates, i
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
