DINOFLAGELLATA 



323 



further division until the upper one has divided for the second time, 

 leaving several open cups; on tunicates. 



A. mycetoides C. (Fig. 130, d, e). On gill-slits of Fritillaria pel- 

 lucida. 



Genus Chytriodinium Chatton. In eggs of planktonic copepods; 

 young individuals grow at the expense of host egg and when fully 

 formed, body divides into many parts, each producing 4 swarmers. 

 Several species. 



C. parasiticum (Dogiel) (Fig. 130, /). In copepod eggs; Naples. 



Genus Trypanodinium Chatton. In copepod eggs; swarmer-stage 

 only known. 



Fig. 131. a, Oodinium ocellatum, recently detached from host gill; 

 b, a free living flagellate form, X760 (Nigrelli); c, d, 0. limneticum, X800 

 (Jacobs). 



T. ovicola C. (Fig. 130, g). Swarmers biflagellate; about 15ju long. 



Genus Duboscqella Chatton. Rounded cell with a large nucleus; 

 parasitic in Tintinnidae. One species. 



D. tiniinnicola (Lohmann) (Fig. 130, h). Intracellular stage oval, 

 about 100^ in diameter with a large nucleus; swarmers biflagellate. 



Genus Haplozoon Dogiel. In gut of polychaetes; mature forms 

 composed of variable number of cells arranged in line or in pyramid; 

 salt water. Many species. 



H. clymenellae (Calkins) (Microtaeniella clymenellae C.) (Fig. 130, 

 i,j). In the intestine of Clymenella torquata; colonial forms consist of 

 250 or more cells; Woods Hole (Shumway, 1924). 



Genus Syndinium Chatton. In gut and body cavity of marine 

 copepods; multinucleate round cysts in gut considered as young 



