APPENDIX D. Ixxxvii 



number of these eggs, observed for several days in succes- 

 sion (their identity was therefore incontestable), became 

 transformed bodily, some into Rotifers, others into Nema- 

 toids. Other eggs presented an individualization of their 

 substance, that is to say, that which, in the preceding case, 

 served to produce a superior organism, became converted 

 into little vesicles which moved about actively within the wall 

 of the ovum, and these little vesicles became as many Mona- 

 dmcB, which escaped from their chamber of incubation/ It is 

 impossible now to follow Dr. Gros into all the details given 

 in his longer memoir ^, which is illustrated by fifteen plates. 



In the life-history of Volvox globaior, according to 

 Dr. Braxton Hicks ^, a pordon of its contents, such as 

 would generally be devoted to the production of ciliated 

 gemmules, may occasionally be converted into a large 

 and distinct Amoeba. Some of the masses, named Zoo- 

 spores, at an ^idvanced age, instead of undergoing a 

 process of self-division and breaking up into forty or fifty 

 small ciliated bodies, considerably increase in size, and 

 gradually assume an irregular outline. These altered 

 bodies present one or two nuclear-like particles in their 

 interior, and, like AincebcE, they are said to exhibit the most 

 distinct movements, accompanied by changes of form. 

 In a subsequent communication^ Dr. Hicks writes: — 'In 

 the autumn of i860 I had an excellent opportunity of 

 verifying my notes, and of tracing the change apparently a 

 step further. Out of a large number of Volvox collected in 

 the south of England, I scarcely found one in which the 

 state alluded to did not exist. In many, twenty of these 

 amceboid bodies could be counted m.oving about immediately 

 beneath the transparent sphere. That they could not., »■- »>^_ 



^ ' Bull, de la Soc. de Natural, de Moscou,' 1847. yO^J^^OR X x 



2 'Journ. of Microsc. Science' i860, p. loi. / ^ 'O '\ 



3 Ibid. 1862, p. 96. /^/-^ -^^^--^ ^ 





