FERTILIZATION AND FRUIT-FORMATION IN CRYPTOGAMS. 



53 



the water. The actual fact is that spermatozoids which come into the vicinity of 

 the spherical ooplasts adhere to them in such large numbers that a sphere is some- 

 times entirely coated with spermatozoids (see fig. 203 *). 



It has also been observed that the spherical ooplasts are set rolling by the 

 adherent spermatozoids, and are thus removed from the places where they pre- 

 viously lay stranded. The fertilizing effect exercised by the spermatozoids, one of 



>^V^^^ '^ 



Fig. 204. — Fertilization and Fruit-formation in Mucorini, Svphonacece, and Floridece. 



1-* Conjugation and fruit-formation in Sporodinia grandis. 5, 6 Vauchcria sessitis. ^ Fruit-rudiment witli trichogyue of 

 Dudresnaya coceinea. s Antlieridia of the same plant with spermatozoids in the act of abiunction. » Fruit of the same. 

 i-*xl80; 6,6x250; ',8x400; Sx 260. ('-» after Bornet. ) 



which, as it appears, coalesces with the ooplasts, consists doubtless in a rearrange- 

 ment of molecules, and the first outwardly visible result of this rearrangement is 

 the envelopment of the ooplast in a tough cell-membrane. The body must now be 

 considered to be a fruit — a unicellular fruit, which remains unaltered in a state of 

 rest for some time, but at length bestiru itself, and stretching out attaches itself 

 firmly to the ground by means of root-like outgrowths. It then divides and gra- 

 dually develops into a fresh Fucus plant. 



In the two cases just described, the ooplasts are not fertilized till after they have 



