2 9 



Fi S- 37- 



DEVELOPMENT OF THE ANTHERIDIUM. The cell which is to produce 

 the Antheridium divides horizontally (to the axis) into a disk-shaped 

 basal cell and a terminal cell which finally becomes nearly spherical, 

 flattened only at the base, where it rests upon the stipe cell. The 

 stipe cell is usually quite short, but occasionally (as in Tolypella stip- 

 itata) it is considerably elongated. 



The terminal cell now di- 

 vides into four, then into 

 eight cells. These eight cells 

 occupy the whole circumfer- 

 ence of the sphere; they now di- 

 vide internally parallel to the 

 surface in such a way that 

 three sets, each of eight cells, 

 form one within the other 

 Fig. 38, "c." These twenty- 

 four cells are thus arranged in 

 eight radii and form three 



spheres one within the other. Fig. 38. 



The superficial cells differ somewhat in shape ; those about the free 

 apex of the sphere come to a point and are triangular in shape, see 

 Fig. 39, "A," while those at the base having the points downward 

 are truncated ; all are arched on the surface to make the sphere and 



