122 



THE PROTOZOA 



applied in a very indirect manner, and he calls the resulting move- 

 ment " conical translation." l 



Fig. 67. Phalansterium digitatum St. [S.KENT.] 

 / Collared cells. 



A peculiar pseudopodial process, the collar, is found in one order 

 of the Flagellidia, the Choanoflagellida. This collar, which forms a 

 cup around the base of the flagellum, is extremely thin, delicate, and 

 transparent, and like a pseudopodium can be altered in shape and 



1 Cf. Delage ('96), p. 305, for a very full discussion. 



