374 



BOTANY. 



366. — The sexual organs consist, as in Coleochwte, of 

 carpogonia and antheridia. The latter are composed of one 

 ■or more mother-cells, situated singly or in groups on the 

 ends of branches {A and B, a, a, Fig. 185). The sperma- 

 tozoids are small, round bodies, which are destitute of cilia, 

 and, as a consequence, incapable of independent movement 

 {A, X, Fig. 185) ; they are carried about by currents of 

 ^ water, and in this way brought to 



the carpogonia. 



367. — The carpogonia are some- 

 what yariable as to their complex- 

 ity, being much more simple in 

 the lower orders than in the high- 

 er. In the genus Nemalion the car- 

 pogonium consists of a single cell 

 {B, I, Fig. 185), resembling Coleo- 

 chmte closely in this respect. It 

 is thickened below, and elongated 

 above into the trichogyne, whicK 

 diilers from that in Coleochmte in 

 Fig. isi.-Teiraspores of Florid- ^ot being opcn at the top. When 

 I. tetrauporee.- After Sachs B,oi the spermatozoids are set free from 



C'oraffina o^inofis ; (, tetraspores '- • t , i li_ \ L^ 



in a cup-Bhaped extremity of a the antheridia they attach tnem- 

 ranc .— er er ey. gelves to the trichogync, as shown 



in Fig. 185 ; the result of this contact of the spermatozoids 

 with the trichogyne is the fertilization of the carpogonium, 

 which immediately enlarges, and at the same time undergoes 

 division into many cells, which grow into short, crowded 

 branches, bearing a spore at the end of each {D and E, 

 Fig. 185). To this growth, which includes the spores and 

 the short branches which bear them, and which resulted from 

 the fertilization of tlie carpogonium, the name of sporocarp is 

 applied. In the genus under consideration the sporocarp is 

 a comparatively simple growth, as compared with the degree 

 of complexity it reaches in some other orders of this class. 



368. — In the genus Lejolisia, the carpogonium, before 

 fertilization, consists of several cells {A, h, Fig. 185) ; the' 

 trichogyne is in connection with certain of the exterior cells 

 ■of the carpogonium, but not directly with its central cell. 



