18G0.] Contributions to Indian Malacology . 125 



terparfc of that in the Sikkim shell, Megalomastoma funiculatum, B. 

 The perfect smoothness of Dip. Nilgirica, and the continuity of the 

 internal peristorne, give it a sub-generic character, yet seem insuffi- 

 cient alone to authorize its separation from Diplomm atina. 



The animal could not be well observed for the vvant of a suffi- 

 eiently powerful mngniíier at hand. It was small, short, and colour- 

 kss, with two small black tentacles. 



4.— Ctclotus Malabakictts, n. s. 

 Testa subaperte umbilicata, depres^o-conica, albida, glabra, nitidula, 

 epidermide decidua cornea, ad anfr. ultimum transverse fusco-strigatá, 

 induta ; spira cónica, ápice acuta ; sutura profunda ; anfr. 4 rotundati, 

 celeriter crescentes, ultimus cylindraceus ; apertura parum obliqua, 

 circularis, prope umbilicum parum sinuata, sup.erne vix anguiata ; 

 perist. dúplex, externum brevissime expansum, internum porrectum, 

 acutum, continuum ; umbilicus perspectivus. Operculum haud immer- 

 sum, dúplex, internum corneum multispirum, externum testaceum, 

 anfractuum marginibus lamella spirali, albida, scabrá ad anfr. exter- 

 nos pereievatá et versus centrum incurvatá, quasi convexa, munitis. 



Diam. maj., 3| m. Ui, 



Ditto min., , 2f ditto. 



Alt., %\ ditto. 



Apert. diam., 11 ditto. 



Hab. sub rupibus et saxis in térra húmida ad margines sylvarum 

 prope Pykara montium " Nilgiri," ad alt. 7000 ped. 



JNearly allied to Cyclotus jilocinctus> Benson, by the peculiarity of 

 its operculum, this shell is distinguished by its smaller size, more 

 depressed form, and less expanded peristorne, by the absence oí' the 

 marked sculpture of O. filocinctus, and by the epidermis being lighter 

 in colour and marked by brovvn transverse streaks on the last whorl. 

 'J hat of C. filocinctus is hispid. The last named shell was first 

 described by Mr. Benson as a Cyclostoma, to vvhich genus it was 

 assigned till lately. The construction of the operculum is very 

 peculiar. The testaceous spiral lamina being very much more raised 

 towards the exterior than towards the centre, and being curved 

 inwards, the interior whorls of the operculum are almost coneealed 

 and the appearance, unless very closely exaniincd, is that of the oper- 



a 



