Text-book of botany, morphological and physiological . Fig. 214 bis.—First stafje of development of the archesjo-nium of Andrenfa (after Kiihn) ; A terminal arrhejroniumarising from the apical cell of the shoot; b b the younjjcstleaves ; B after the formation of the central cell and stig-matic cell; C transverse section of the young ventralportion. HEP A TICM. 301 The sporogonium also originates in different ways. The fertilised oosphereis always first divided in the archegonium into two cells, the upper of which,facing the neck, forms the growing apical cell; but this divides in very differen
Text-book of botany, morphological and physiological . Fig. 214 bis.—First stafje of development of the archesjo-nium of Andrenfa (after Kiihn) ; A terminal arrhejroniumarising from the apical cell of the shoot; b b the younjjcstleaves ; B after the formation of the central cell and stig-matic cell; C transverse section of the young ventralportion. HEP A TICM. 301 The sporogonium also originates in different ways. The fertilised oosphereis always first divided in the archegonium into two cells, the upper of which,facing the neck, forms the growing apical cell; but this divides in very differentways in the different groups:—in Anthoceros by oblique walls inclined in fourdirections; in the IMarchantiese and Ricciese by walls inclined alternately in twodirections; while the sporogonium of the Jungermanniese contains, even in its veryearliest stage, four apical cells lying beside one another like octants of a sphere,. FlC. 215.—Later stage in the development of the archegonia and origin of the sporogonium of Marchantza poly-morpha; /,//, young archegonia ; III,II, after absorption of the axial row of cells of the neck ; ^when ready for fer-tilisation ; K/-////the cells of the mouth of the neck a-relaxed after fertilisation; the fertilised oosphere y shows itsfirst divisions. In these figures si is the lowest cell of the axial row in the neck which is last converted into mucilage; e inI-IVl\\e central cell, in Athe unfertilised oosphere ; // in V-VII the perianth in process of development; /^ theunripe sporogonium in the ventral portion of the archegonium which has developed into the calyptra; a neck of thearchegonium ; f wall of the sporogonium ; st its stalk ; inside the sporogonium are the young elaters arranged in rays,among them the spores. (/-F///X300, IX about 30.) which divide simultaneously by horizontal septa. When the young sporogoniumhas in this manner attained its destined height, and
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
