222 



BOTANY. 



act, is that within a short time a thick coat of cellulose is 

 formed over the new cell, thus producing a zygospore (H, 

 Fig. 149). After a long period of rest, these zygospores 



Fig. 149. Pnndorina Morum. A, non-sexual colony (or ceenobium) of 16 zoogoni- 

 dia ; a, red spot ; b, transparent anterior end of zoogonidium, to which the two 

 cilia are attached. 



B, sixteen young sexual colonies about to leave the gelatinous wall. 



<7and Z>, colonies of sexual zoospores escaping. 



IS, F, <?, conjugating zoospores 



ff, zygospore in resting stage (red). 



J, A, germinating zygospore, the contents escaping as a large red ciliated swarm- 

 epore. 



L. new colony formed by the division of K, very young stage. 



M, the same colony as Z, in a further stage of development. After OZrsted. 



germinate by the bursting of the coat (exospore), when the 

 protoplasmic contents escape as a ciliated swarm-spore (A', 

 Fig. 149). After swimming about for some time, the swarm- 



