126 



Records of the Indian Miiseiiiii. [\"oi,. XXII, 



its much smaller size, narrower and less inflated body-whorl and 

 the larger but relatively broader mouth. 



Stenothyra ornata, sp. nov. 

 Plate XVI, figs. I, 2. 



The shell in this species is relativeh^ large, conoidal-ovate in 

 form, and of a brownish colour. The apex is acutely pointed, and 

 the shell has 5| whorls. The suture is moderately' impressed, 

 somewhat oblique but irregular. The whorls of the spire are dis- 

 tinctly keeled in the middle and a continuation of the keel is to be 

 made out on the body-whorl as well ; they increase regularly in 

 size but owing to their keeled nature do not appear to be very 

 much swollen. The first two whorls are rather minute, the third 

 is about as broad as the penultimate, which is somewhat band- 

 shaped. The body- whorl, as seen from the dorsal side, is sub- 

 quadrate, ventrally it appears to be somewhat ovoidal with the 

 inverted apex sharply truncated. The mouth of the shell is very 

 minute, oblique and regularl}' subcircular. The rim of the mouth 

 does not project at all and the shell is not umbilicate. All the whorls 

 are covered with a clayey deposit, but in some places show distinct 

 vertical vermiform striae of a darker colour. The last 4 whorls 

 have a persistent spiral row of fairly large, blunt, flattened, horny 

 spines in the region of the keel ; the spines are directed towards 

 the apex and are of a blackish colour. 



Measurements of type-shell (in millimetres). 



Length . . . . . . • • 5 



Breadth of the body-whorl .. ., 3"2 



Length of the spire (dorsal view) . . . . 27 



Aperture . . . , . . . . i"3 



We figure the radular teeth. 



Type-specimen. — No. M 1 1565/2 in the collections of the Zoolog- 

 ical .Survey of India 

 (Indian Museum). 



Locality. — Two shells of 

 this species were collected 

 by Dr. S. W. Kemp in a 

 pool of brackish water at 

 Dhappa near Calcutta. 



Remarks. — The species 

 is closely allied to .S. deliae 

 (Benson) and S. echinata, 

 Annandale and Prashad, 

 but is distinguished by the 

 larger and more acute 

 spire, the form of the 

 body- whorl, the keeled 

 nature of the whorls, the sculpture and by the comparatively shorter 

 and more circular mouth. 



Te.kt-fk; 



Benson. 



(a) S. 



{b) S 



^^ 



I. — Radular tcctli of Steiiothyi-d. 



(S.) vriiata, sp now x .'50. 

 {A.) miliacea {t<ey\\\) X500. 



