344 SPOEOZOA. 



290. Thelohanellus seni (Southwell & Prashad). (Fig. 170.) 



■fMyxobolus seni, Southwell & Prashad, 1918, p. 347, pi. xi, figs. 28- 



31. 

 Thelohanellus seni. Kudo, 1920, pp. 132-3 ; 1933, p. 210. 



Cyst elongated, ellipsoidal, whitish, with black scattered 

 granules on the surface. Spore oval, pointed at the anterior 

 end and much wider behind. Two valves, suture shghtly 

 thickened. Polar capsule single, with a much-coiled filament, 

 lodinophilous vacuole present. 



Fig. 170. — Spore of Thelohanellus seni (Southwell & Prashad). 

 (After Southwell and Prashad.) 



Dimensions. — Cysts 4-7-5-4 mm. by 2-9-3-7 mm. ; spores 

 13-2-13-6/i. by 10-l-10-3ft ; polar capsule about 4/x in length, 

 filament 43/i in the extruded condition. 



Habitat. — On the median and caudal fins of Labeo rohita 

 (Ham.-Buch.) : Bengal, Mirpur, Dacca. 



Genus HENNEGUYA Thelohan, 1892. 



Henneguya, Thelohan, 1892, pp. 167, 176 ; 1895, p. 352. 



Myxobolus (part), Gurley, 1893, p. 418 ; Cohn, 1896, pp. 227-72. 



Henneguya, Labbe, 1899, pp. 101-4 ; Minchin, 1903, pp. 286, 296; 

 1912, pp. 409, 426 ; Kudo, 1920, pp. 158-73, 198-9 ; Wenyon, 

 1926, p. 728; Reichenow, 1929, pp. 1059, 1072; Kudo, 1931, 

 pp. 312-13 ; 1933, pp. 198, 210-12 ; Calkins, 1933, p. 568 ; 

 Reichenow, 1935, p. 388. 



Spores ovoid al ; flattened. With a single or double caudal 

 prolongation. Two pjTiform polar capsules at the anterior 

 end. Monosporous, disporous or polysporous. Sporoplasm 

 contains an lodinophilous vacuole. Mostly histozoic (a few 

 coelozoic) parasites in freshwater Fish ; one species in 

 a marine Fish. 



Key to Indian Species. 



1 (2). Cysts attached to the gill-filaments of [p. 345. 



the host H. ophiocephali Chak., 



2 (2). Cysts in the bulbus arteriosus of the [p. 345. 



host H. otolithi Ganapati, 



