io2iJ. N. Annandai.k : Indian Planorbidae. j6 5 



Subfamily BULLININAE (JSIDORINAE). 



The only living Indian genus is Camploceras Benson, but in 

 late cretaceous times the gigantic Bullinus (Plalyphysa) prinsepii 

 (Hislop) and the same author's " J'hysa" elongaia, for which a 

 new genus will ultimately have to be created in the same sub- 

 family, were dominant forms in the Indian freshwater fauna. 



Genus Camptoceras Benson (184 3). 



mm. Camptoceras Annandale & Prashnd, fonrn. As. Soc. Rcngal 



(n.s.) XVI, p. 457. 

 1919. Camptoceras, /»/., ibid., XVII, p, 27. 



Four Indian and one Japanese species are now known, and I 

 have another, as }'et undescribed, from the Southern Shan States, 

 where it was found sub fossil. 



The external structure of the animal is very like that of 

 Gyraulus except that there is a large anal siphon constructed of a 

 leaf-shaped epipodium which is coiled up spirally to form a funnel 

 each time the animal expands. This has been observed both in 

 the Japanese and in one of the Indian forms. The blood is deep 

 red. Very little is known of the genitalia, but there is no penial 

 stylet or flagellum. The jaws resemble those of Planorbis and the 

 radula is of normal Planorbid type. The pseudobranch is simple. 



The type-species is C. terebra Benson from the United Pro- 

 vinces. Other Indian species are C. ansteni and C. lineatum Blan- 

 ford from Eastern Bengal, C. subspinosum Annand. & Prasbad 

 from Kashmir. C. lineatum has also been found in Manipur, 

 Assam. 



The genus may be divided into two groups as follows : — 



Camptocerata i,ineata. vShell ovate but dissolute, with 

 spiral lines of minute chaetae. 



Species — C. lineatum and C. subspinosum. 



Camptocerata terebrae. Shell definitely cornucopia-shaped, 

 without chaetae. 



Species — C. terebra, C. austeni, C. hirasci (Japan) and an 

 undescribed subfossil Burmese species. 



