200 



BIOLOGY OF THE PROTOZOA 



others possess no chromatophores at all, but still retain the pyrenoids 

 characteristic of their colored allied forms {Tetrahleyharis); others 

 retain the stigmata characteristic of chlorophyll-bearing types, but 

 possess no chromatophores, and still others possess neither stigmata, 

 pyrenoids nor chromatophores, but contain assimilation products 

 which are characteristic of the most nearly related colored forms 

 {Chilomonas and Cryptomonas, Polytoma and CJdamydomonas)." 

 Loc. cit. p. 11. 



In addition to combined autotrophic and sai)rophytic modes of 

 nutrition, some types of flagellates, especially amongst the Chryso- 

 monadida combine holophytic nutrition with holozoic. Here, in 

 the simplest cases, the intake of solid particles is effected by pseudo- 

 podia, either lobose in type or branched (rhizopodia). These may 



Fig. 94. 



-Cyrtophora pedicellafa and Palalinella cyrlophora; flagellates with tentacles 

 and exogenous buds. (After Pascher.) 



arise from any part of the cell or may be, with the gastric vacuole, 

 confined to the anterior end as in Dinobryon (Fig. 126, p. 259). 

 More complex and more differentiated pseudopodia are found 

 amongst the Cyrtophorida:; of the Chrysomonadida. In Cyrtophora 

 pedicellata the cell body, with its single cup-shaped yellow chromato- 

 phore, is in the form of an inverted pyramid attached by stalk at 

 the apex while the broader anterior end l)ears a single flagellum and 



