354 



BOTANT. 



below, where there are two layers. The neck of the arche- 

 gonium at first contains an axial row of cells, but these 

 become dissolved and transformed into a mucilaginous mass 



just before the time of 

 fertilization. The germ- 

 cell lies in the lower 

 swollen portion of the ar- 

 chegonium ; it consists of 

 a naked rounded mass of 

 protoplasm. At the time 

 of fertilization the upper- 

 most cells of the neck of 

 the archegonium diverge 

 from one another, and 

 thus form an open chan- 

 nel to the germ-cell. 



463. Fertilization 

 takes place in the water, 

 or in the presence of a 

 considerable amount of 

 moisture. The spermato- 

 zoids, which are produced 

 in great numbers, move 

 through the water by 

 means of their vibratile 

 cilia, and some of them 

 find their way down the 

 channels of the archego- 



Fte. m-Developtnent of the snorogonium nia > where tnC J Ullit thcir 



otlfaHahwromttrtca A longitudinal sec- substance Avith the eerm- 



tion of the archegonium, b, b, shortly after fer- 

 tilization ; h, neck ; /, iipioil portion of young cells. As a result Ol this 

 sporogonium; f, basal portion of young sporo- 



goniiim. 5, vertical section of a female flower; Union, the germ-Cell SU1'- 



/', young sporoiroiiium elongating, and carrving , ., , .,, .. 



up the remains of the old arclu-goninm, c (now I'OUllds itself Wltll a Wall 



called tlie calyptru) ; h, neck of old archego- < 11 i i 



nium. 6', a later btuge of the sa.nc. Invalid of Cellulose, and SOOU Ull- 



C the sporogonia are seen to he growing down- f l ovrrrin -, /livicion in viriona 



ward into the tissues of the leafy stem A X tlGlgOCb dl\ 1S1O1L 111 A dl 1OU8 



600 ; B and c much less.-After Sachs. directions, giving rise to a 



many-celled mass, the young sporogonium (/, /', Fig. 243, 

 A). In most Mosses the young sporogonium elongates rap- 

 idly, and while its upper end carries up the remains of 



