1386 Mr. W.H. Benson on a new Genus of Auriculacea. 
XVII.— Characters of Coilostele, an undescribed Genus of Auri- 
culacea (?), and of Species of Helix, Pupa, and Ancylus, from 
India, West Africa, and Ceylon. By W. H. Benson, Esq. 
Co1LostELE, B., nov. gen. 
Testa imperforata, elongato-cylindrica; axis columellaris interna 
spire obsoleta. Apertura semiovata; margine columellari superne 
oblique subspiraliter uniplicata. 
Coilostele scalaris, B. 
C. testa imperforata, elongato-cylindrica, leevi, hyalina, nitida ; spira 
elongata, gradatim scalariter attenuata, apice obtuso, sutura pro- 
funda ; anfractibus 6, convexiusculis, superne obtuse angulatis, 
penultimo cylindraceo ; apertura subobliqua, semiovata, subpyri- 
formi; peristomate tenui, recto, marginibus remotis, margine 
columellari crassiusculo, plica spirali obliqua elongata superne 
intrante munito. 
Long. 3, diam. vix 1 mill. Apert. $, lata 3 mill. 
Habitat ad Humeerpore, Bundelkhund, prope ripas fluviorum Jumna 
et Betwa. 
I discovered this shell, in October 1826, in the sand of the 
Betwa river, while searching for Achatina Balanus, of which I 
had taken a specimen in the aperture of a derelict Helix; and 
after a few days I took dead specimens, with the same minute 
Achatina, among the clay-covered roots of a large tree which 
had fallen in the peafowl jungle on the left bank of the Jumna 
opposite to Humeerpore, and in a dried hollow near it, whither 
those shells had been washed in the rains with Bulimus gracilis, 
Hutton. In January 1839 I took, I believe, a single specimen 
among the porphyritic and greenstone rocks of the singular 
crater-like hill of Khaneen, sixteen miles south of Hansi, in the 
Delhi district, but broke it before I could examine it under a 
lens. 
In a list published in the Calcutta ‘ Gleanings in Science’ of 
1829 I set this shell down as a minute Pupa; but on observing 
that the spiral column was obsolete or absorbed, as in the genus 
Pythia (Scarabus), 1 came to the conclusion that the form really 
belongs to the family of Auriculacea. I the other inland 
genus, Carychium, the spiral column is intaét, except close to the 
summit, althotigh in the littorine genera Alexia, Auricula, Me- 
lampus, and Cassidula 1 find the internal structure of the spire 
similar to that of Cozlostele and Pythia. 
In C. scalaris the aperture has some resemblance to that of 
Jaminia, Say, a North-American marine operculate genus, which 
Kiister included in the Auriculacea, but which is now referred 
to the Pyramidellide. 
Shortly before 1853, Capt. T. Hutton collected specimens of 
a 
