130 ROMANCE OF LOW LIFE AMONGST PLANTS. 



spaces between, and become in fact the young 

 conidia of the new individual. Several of these 

 young spheres appear almost simultaneously within 

 the parent, so that they are often closely packed ; 

 and yet each individual gonidium soon exhibits its 

 own pair of movable hairs. In this state the young 

 spheres await the rupture of the parent sphere to 

 escape into the water and commence a separate ex- 

 istence. The opening in the wall of the old volvox 

 is usually smaller than the diameter of the young 

 globes, so that the latter are compressed in their 

 exit, but at once resume the globular form. After 

 a little time, the parent, having accomplished its 

 mission, decays and dissolves away. 



The process, as above described, is maintained 

 throughout the summer, and is practically a sort of 

 vegetative reproduction by division without any 

 intervention of sexuality. It is, in fact, an asexual 

 reproduction, which may be repeated many times ; 

 but at length is replaced, in the autumn, by a true 

 sexual process. In this we recognize the pheno- 

 menon of an alternation of generations ; several 

 generations are produced asexually by division, then 

 a sexual generation, ending in a hybernating oospore, 

 which in turn produces another series of asexual 

 generations. 



Some authors recognize two varieties, or even two 

 species, of Volvox, in one of which the male and 

 female elements are found on different spheres, in 

 the other the male and female organs are found on 

 the same sphere. 



The female cells, when they are present, in the 



