POLYMASTIGINA 311 



lar to Trichomonas vaginalis; but 3 anterior flagella; body about 

 15m by 5/i; transmission by sexual act, from cow to bull or bull to 

 cow; in infected cow conception temporarily or permanently is sus- 

 pended or death of foetus occurs. 



T. fecalis Cleveland. 5m by 4m to 12m by 6m; average dimensions 

 8.5m by 5.7m; axostyle long, protruding 1/3-1/2 the body length 

 from the posterior end; of 3 flagella, one is longer and less active 

 than the other two; in the faeces of man. Its remarkable adapta- 

 bility observed by Cleveland was noted elsewhere (p. 30). 



T. batrachorum (Perty). Ovoid; 14-18m by 6-10m; in frog gut. 



T. augusta Alexeieff. Spindle-form; 18-22m by 8-14m; in frog gut. 



Genus Tricercomitus Kirby. Small; 3 anterior flagella; a long 

 trailing fiagellum, adhering to body; nucleus anterior, without 

 endosome; blepharoplast large, with a parabasal body and an axial 

 filament; parasitic. 



T. termopsidis K. (Fig. 146, d, e). 4-1 2m by 2-3m; anterior flagella 

 6-20m long; trailing fiagellum 19-65m long; in gut of Zoolermopsis 

 angusticollis, Z. nevadensis and Z. laticeps; California and Arizona. 



Genus Pentatrichomonas Mesnil. Similar to Trichomonas, but 

 with 5 free anterior flagella. 



P. hengalensis Chatterjee. 9-20m by 7-14m; in human intestine. 

 Kirby (1943) observed that of the five flagella, four arise from the 

 end of a columnar (1-2m long) extension, while the fifth fiagellum is 

 a little shorter and takes its origin about 1m behind the extension. 



Genus Pentatrichomonoides Kirby. Five anterior flagella and the 

 undulating membrane; axostyle very slightly developed; fusiform 

 parabasal body; nucleus separated from the anterior blepharoplast; 

 in termite gut. 



P. scroa K. (Fig. 146,/). 14-45m by 6-15m; in Cryptotermes dudleyi 

 and Lohitermes longicollis. 



Genus Pseudotrypanosoma Grassi. Large, elongate; 3 anterior 

 flagella; undulating membrane; slender axostyle; band-like structure 

 between nucleus and blepharoplast; parabasal body long, narrow; 

 in termite gut. 



P. giganteum G. (Fig. 146, g). 55-1 11m long (Grassi); 145-205m by 

 20-40m; anterior flagella about 30m long (Kirby); in gut of Poro- 

 termes adamsoni and P. grandis. 



Suborder 2 Diplomonadina 



The suborder consists of a number of binucleate flagellates pos- 

 sessing bilateral symmetry. 



