Phylum Pyrrhophyta 



[97 



Order Cryptomonadida Calkins Biol. Prot. 265 (1926). 



Orders Cryptocapsales and Cryptococcales Pascher in Beih. bot. Centralbl 48, 

 Abt. 2: 325 (1931). 

 Solitary (exceptionally colonial) cells, usually with one or two plastids of various 

 colors, usually observed in the motile condition, then naked, of dorsiventral (excep- 

 tionally isobilateral) symmetry, with two anterior flagella which are not markedly 

 differentiated or not respectively anterior and circumferential. 



The resting nucleus contains a karyosome, i. e., a globule which occupies most of 



t 



t>.>. 





Fig. 18. — a, Cryptomonas sp. b, Rhodomonas baltica after Kylin ( 1935 ) . c, Chi- 

 lomonas Parmecium. d, Cyathomonas sp. e, Sennia sp. f. Vegetative cell, and 

 g, zoospore of Paradinium Pouchetii after Chatton (1920). All x 1,000. 



its volume and contains most of the chromatin. Dangeard (1910) and Belar (1916) 

 have observed details of mitosis. The numerous chromosomes appear within an 

 intact nuclear membrane and form a disk- or drum-shaped figure with its axis at 

 right angles to the axis of the cell. No granule more massive than the chromosomes 

 persists and divides with them. 



About thirty species are known. They may be treated as five families. 

 1. Flagellate cells elongate, with one plane 

 of symmetry. 



2. Not parasitic, flagella not markedly dif- 

 ferentiated. 



3. Non-motile in the vegetative con- 

 dition Family 1. Cryptococcacea. 



3. Flagellate in the vegetative con- 

 dition Family 2. Cryptomonadina. 



