. A handbook of cryptogamic botany. Cryptogams. RHIZOCARPE^ 27 lical point becomes cut off by a septum, forming the neck-canal-cell. ow this a second very small portion of the central cell is again cut off form the ventral canal-cell, so that the canal now consists of two s. These two cells become transformed into mucilage, which escapes forcing apart the four apical or stigmatic cells, leaving an open canal the meantime the protoplasm of the large basal portion of the central has become transformed by contraction into the oosphere. The legone is now ready for impregnation, the antherozoids re
. A handbook of cryptogamic botany. Cryptogams. RHIZOCARPE^ 27 lical point becomes cut off by a septum, forming the neck-canal-cell. ow this a second very small portion of the central cell is again cut off form the ventral canal-cell, so that the canal now consists of two s. These two cells become transformed into mucilage, which escapes forcing apart the four apical or stigmatic cells, leaving an open canal the meantime the protoplasm of the large basal portion of the central has become transformed by contraction into the oosphere. The legone is now ready for impregnation, the antherozoids reaching the phere through a funnel-shaped depression in the epispore and the n canal. After fertilisation the canal again closes up by the expan- 1 of the stigmatic cells. The begone of Azolla resembles that aalvinia in all essential points. The male prothallium of Salvinia educed to a mere rudiment. The xospores lie imbedded in a mass ardened, granular, frothy mucilage, ned by the disorganisation of the stal cells. They do not escape n this mucilage, but the endospore sach develops into a tubular fila- it which pierces through the muci- ; and the wall of the sporange. ; extremity of this filament which jects outside the sporange is /ed, and becomes cut off by a tum. The lower and larger of the cells thus formed is regarded as dimentary prothallium; the termi- cell, which again divides into two, a rudimentary antherid. The protoplasm of each of the two leridial cells divides into four, and each of these eight masses of :oplasm escapes as an antherozoid. Each antherozoid is a corkscrew- coil of protoplasm, bearing vibratile cilia of great length at its ider extremity. To the same extremity is attached a vesicle, corn- ed of a portion of the protoplasm of the ahtheridial cells which not used up in the formation of the antherozoids, and which does leave the antherozoid during the period of its ' swarming.' The developrhent of the multicellular embryo from the fertilised )erm has be
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