454 



BOTANICAL GAZETTE 



[DECEMBER 



asm 



bution of plastids. 



which 



vicinity 



pigment 



pigment 



cilia of unequal length are borne; the long one being directed toward 

 the anterior end, i . 5 times the long diameter of the gamete, and 

 the short one in the opposite direction about equal in length to the 



6 



7 



Figs. 6, 7. — Cutleria multifida: fig. 6, a filament bearing two female gametangia; 

 fig. 7, female gametangia near maturity; a consists of 7 tiers of mother cells, and 

 ft of 4 tiers. 



diameter of the gamete. The long axis of the female gamete is 

 26.2 /a. The female gamete is actively motile when discharged, 

 - but after a while the movement becomes sluggish, the shape becomes 

 spherical (fig. 8, c), and the cilia are withdrawn. 



Development of female gametangia. — Like the male gametangium, 

 the female gametangium arises from a superficial cell of the thallus. 

 One of the superficial cells begins to grow more rapidly than the 

 others (fig. 53) and a typical mitosis takes place, which gives rise 



