the Cyclostomacea of Eastern Asia. 453 
and its associated genera, Rhiostoma, Spiraculum, &c., must fall 
into the same group. 
This little section, the species of which also agree in their 
velvety epidermis, when in good condition, appears to coincide 
in so many points with the subgenus Myzostoma of Troschel, 
that it may probably be classed with that section. The charac- 
ters of the Burmese species are 
Testa late umbilicata, depressa, subdiscoidea, epidermide fusca 
hispidula induta; anfractibus rotundatis. Apertura circularis, 
peristomate incrassato. Operculum crassum, corneum, anfractuum 
margiuibus lamellatim elevatis. 
The species included are— 
C. pinnulifer, Bens. Khasi Hills. 
C. calyx, Bens. Molmain*. 
C. hispidulus, W. Blanf. Ava. 
III. The discoidal species of India and Ceylon, with thin 
opercula. These are— 
C. phenotopicus, Bens. Darjiling. 
C. ravidus, Bens. Nilgiri Hills and Ceylon. 
C. stenostomus, Sow. Nilgiri Hills. 
C. deplanatus, Pfr. Nuilgiri Hills. 
C. annulatus, Trosch. Ceylon. 
C. Bairdii, Pfr. Ceylon; 
and one or two Ceylonese species with which I am unacquainted. 
C. Bairdii, C. stenostomus, and C. deplanatus are so closely 
allied as to be scarcely more than local varieties; and the same 
is the case with C. ravidus and C. annulatus. 
IV. A group of shells arranged by Pfeiffer under Leptopoma, 
but differing from the species of that genus in the non-expanded 
peristome, in the rounder whorls, more globose forms, slower 
increase in the size of the whorls, and consequent comparative 
smallness of the mouth, and in the tendency to a rapid and 
irregular descent of the last whorl in aged specimens. The 
species are peculiar to Ceylon and Southern India, and comprise 
the following :— 
C. celoconus, Bens. Southern India. 
C. malleatus, W. Blanf. Shevroy and Nilgiri Hills. 
C. halophilus, Bens. Ceylon. 
C. orophilus, Bens. Ceylon; 
and three or four other Ceylonese species, the differences be- 
tween which and the two last mentioned are very minute. 
* The locality is, I believe, erroneously given as Akoutoung, Pegu. I 
have collected largely and repeatedly at that locality, but never met with 
a specimen; whereas the shell is abundant at Molmain. 
