132 ROMANCE OF LOW LIFE AMONGST PLANTS. 



it a stellate appearance. Simultaneously with this 

 the green contents of the oogonia change to orange 

 red, of an oily nature, and the oospore becomes a 

 resting spore. The mother- colony breaks up, whilst 

 the thick-coated reddish oospores sink to the bottom 

 to hibernate, and this is the termination of another 

 generation. This determines the question as to what 

 becomes of the volvox during the winter, and we 

 must follow the oospores through their period of rest 

 to ascertain how they reappear in the spring. 



In the spring the resting spore gradually awakens 

 to new life, and after some minor preparations the 

 outer coating is ruptured, whilst the contents en- 

 closed in an inner membrane protrude. These con- 

 tents are soon observed to divide gradually into from 

 two to sixteen, or more, small cells, which become 

 again of a bright green colour, each one bearing at 

 one extremity two movable hairs. These cells are 

 gradually driven further apart from each other, by the 

 interposition of gelatine, when, as the outer membrane 

 disappears, the active hairs come into full play, and 

 the young volvox is fairly launched into life. " The 

 resting spores of volvox, therefore, germinate in 

 water, and each of them produces a single colony 

 by a process of segmentation, identical with that 

 which gives rise to a daughter-colony, at the expense 

 of a cell of the mother-colony." 



With this initial step the cycle of non-sexual genera- 

 tions again commence, and is continued through the 

 summer, until, at its close, resting spores are again 

 formed by means of sexual developments, so as to be 

 able to undergo the vicissitudes of winter. 



