THE BEGIAWINGS OF LIFE. 489 



vesicules; ranimalisation progressa^ mais non plus en 

 faveur d-'un organisme individuel superieur, et au lieu 

 de voir le contenu de cette chrysalide donner un Rota- 

 toire comme leurs congeneres anterieures, on vit le 

 vitellus se resoudre a I'interieur du cocon en des organ- 

 ismes inferieurs_, ou pousser a Fexterieur du cocon des 

 utricules hiles, qui devenaient la source d'une nouvelle 

 generation d'lnfusoires utriculeux 1/ 



But quite recently I was fortunate enough to observe 

 somewhat similar phenomena. The substance of some 

 of the large thin-walled ' eggs ' of Hydatina senta was 

 seen to have undergone segmentation into about sixteen 

 spheres, each -^^-^-^ in diameter. The external layers 

 of these soon became condensed into cyst -walls, whilst 

 the internal substance of each of them, after under- 

 going a series of molecular changes, resolved itself 

 into an embryo Oxytricha, some of which might be 

 seen revolving within their cysts. Some of this batch 

 of Rotifer ^ eggs' were seen to be filled with such sphe- 

 roidal masses, whilst others were observed in which a 

 few of the embryos had escaped from their cysts, and 

 were swimming about as well-marked specimens of 

 Oxytricha within the thin investing membrane of the 

 Rotifer egg 2. And on another occasion, when some 



^ Similar utricles developing into Vorticellse may, moreover, according 

 to Dr. Gros, be budded out even from Euglense which have undergone 

 no decolourization, and which, therefore, have no actual relation to 

 Rotifers. (See loc. cit., p. 475, PI. C, fig. 10.) 



2 These organisms were almost precisely similar to those which pro- 

 ceeded from the Chlorococcus vesicles (see p. 467). 



