soit. iMO.] THE GERMINATION AND DEVELOPMENT. 181 



In the latter part of the fourth week, the oospores are 

 formed in a considerable number. They are now so numerous 

 that they ma}- be found here and there on the bottom of 

 the beaker in heaps as minute brown spots to the naked 

 eye. 



As the antheridia and oogoniaare matured, the protonema- 

 like sporelings go to decay sooner or later. Withering of the 

 hairs foreruns as a symptom of the decaying. In the sixth 

 week, the filaments are still to be seen, of course without hairs, 

 with some cells containing pale chromoplasts. In the seventh 

 week, the cells are all empty. 



The oospores take a very short resting period. Within a 

 few days after they have been detached from the mother-cells, 

 they begin to germinate. The process of the germination is 

 essentially like that of the resting stage of the zoospores. I could 

 trace their development till they formed three-celled filaments, 

 which took place at the end of the fifth week. They remained 

 unchanged in this stage for several weeks since then, when they 

 w^ent to decay and I was obliged to give up the culture. 



As may be understood from the above description, in the 

 fifth and sixth week, the beaker contained the half-withered 

 sporelings generated from the zoospores, young sporelings from 

 the oospores, and the ungerminated oospores mingled together. 



If the oospores continue to develop in nature and form the 

 frond.s of PhyUitis Fascia KtJTZ. familiar to us, the c£espitose 

 habit of the plant will be very likely due to the aggregations 

 of the oospores and not of the zoospores. This has a greater 

 probability when we consider the fact that several oospores are 

 generated from single sporeling. 



It has already been stated above that the sexuality of the 

 spores in the sori of the Encoeliaceous plants appears to be not 

 the same in all cases. The sori of Scytosipbon and PhyUitis 

 resemble each other so much that no one has ever doubted 

 their being of the same nature. The swarmspores of PhyUitis, 

 however, as has been reported by Keinke^^ and verified by the 



1) 1. c. 



