518 THE BEGINNINGS OF LIFE. 



inversely proportionate to one another. In portions 

 that were green, the algoid aggregations were numerous, 

 and the 'winter-eggs' were scarce; whilst, as more 

 and more decolourized portions of the previously green 

 pellicle were selected for examination, the c eggs' 

 increased in number and the green Chlorococcus-heaps 

 became scarcer and scarcer. 



But even before I had thoroughly satisfied myself 

 concerning this mode of origin of Hydatina, I had had 

 evidence almost as convincing which at the time 

 I could scarcely bring myself to credit that these 

 splendid Rotifers are occasionally produced, in an 

 almost similar manner, from aggregations of small 

 Euglenae l entering into the composition of a Euglena- 

 pellicle. Brownish egg-like masses, about ^JV in 

 length, were apt to appear imbedded in the very 

 midst of the pellicle. They were somewhat variable 

 in size, and, like the bodies we have just been de- 

 scribing, they were more decidedly brown in colour than 

 those which are produced within an adult Hydatina. 

 The difference, however, was not nearly so marked 

 between the ordinary gemmae and the so-called c winter- 

 eggs ' formed from the substance of the Euglena-pellicle, 

 as between gernmse and the similar c eggs' derived from 

 Chlorococcus-heaps. But during the development of 

 such bodies in the Euglena-pellicle, there was the same 

 absence of an investing membrane in the early stages 

 as had been noted in their formation from Chlorococcus 

 1 About -rsm" in diameter* 



