THE BEGINNINGS OF LIFE. 505 



Dr. Gros, such is actually the case. Although as a 

 general rule the Actinophrys tends to become converted 

 into one or other of the Ciliated Infusoria, and exists 

 in this intermediate state for a time before assuming 

 the form of a Rotifer^, still this is not always so. 

 Occasionally a large Actinophrys may be transformed 

 at once into a Rotifer or some other higher form. 

 Their ultimate fate seems to depend principally upon 

 their origin, size, and general vigour. The largest 

 specimens may give off buds which become converted 

 into Ciliated Infusoria 2^ although the parent mass sub- 

 sequently develops into one or other of the more com- 

 plex Rotifers. Dr. Gros says: — <^Quand la metamor- 

 phose ascendante approche, ils retirent successivement 

 tous leur cils • diminutifs etonnants de sugoirs polypiens 

 (Pi. L, fig. 9) et se transforment directement en Rota- 

 toires.' And elsewhere^, the same observer also speaks 

 of the direct conversion of large Euglen^ into AmcebiE 

 and Actinophrys, and of the ultimate transformation 

 of some of them into Rotifers. 



There are, however, other facts not yet stated which 

 suffice to give a double interest to the transformations 

 of Actinophrys and of Ciliated Infusoria into Rotifers. 



^ Speaking of the large specimens of Actinophrys, Dr. Gros says (loc. 

 cit., p 436) : — 'Un trait qui est g«^neral, c'est qu'ils tendent tous vers les 

 utriculeux cilies, et ces dernieres pousseront aux Rotatoires ovigeres ou 

 pangeniques selon la derivance.' (See also p. 451.) 



2 Loc. cit., p. 436, PI. J, fig. 16. 



3 Loc. cit., pp. 331 and 335. 



