MOLLUSCA. 
17 
base ; whorls seven, closely wound ; the last scarcely, if at all, broader than the previous one, 
more or less subangulate at the periphery : base convex, distinctly excavated round a deep 
narrow umbilicus ; aperture very shallow, the outer margin distinctly thickened, slightly 
subangulate in the middle ; columella very slightly reflected, oblique, evenly rounded, without 
any angulation at the base, in this character resembling N. splendens and differing from 
N. prona. I know of no Indian species like this interesting little shell ; in shape it somewhat 
resembles the smooth N. woodiana. Diam. 11|, alt. 5|, axis ; apert. lat. 5-J- mm. 
Dr. Stoliczka found a few specimens alive at Sonamarg ; he notes that the animal is 
provided with a mucous pore. 
8. Nanina (Macrochlamys) prona, n. sp. 
Shell small, of the same group as N. petrosa, Ilutt., &c., but with closer wound whorls ; 
it is a form which apparently is widely spread throughout the North-Western Himalayas, as 
the Museum possesses numerous specimens from Simla, Masuri, Naini Tal and Sahdranpur ; 
two specimens, found by Colonel Godwin- Austen in the Daffla Hills, also apparently belong 
here. A very similar small form, but I think specifically distinct, is also found in the Bombay 
Presidency. Dr. Stoliezka’s specimens from Murree are all young, or in bad preservation ; 
I have therefore determined on not naming the species from his Murree specimens, but take 
as my type the common North-West Himalayan form, the animal of which is known and 
which is usually recorded in collections as N. petrosa. Colonel God win- Austen informs me 
that Hutton himself transferred his own name petrosa from the Mirzapur shell to the 
Masuri one, on the strength of Benson’s statement that the former was identical with the 
Calcutta N. vitrinoides, in which, as already stated, Benson was quite wrong. This 
species is . not figured in the “ Conchologia Indica,” as far as I can see. Whorls six, closely 
wound, the last only slightly deflected, sometimes not at all, in which case, of course, the 
aperture is quite vertical ; spire almost or quite flat ; periphery rounded ; umbilicus resembling 
that of N. petrosa, more open than in all the other allied species ; horny-brown colour, smooth 
and polished above and below ; margins of aperture distinctly, but slightly thickened. Type 
from Naini Tal: diam. 12, axis 4J, alt. 5|- ; apert. lat. 6, alt. 4f mm. 
9. Nanina (Bensonia) monticola, Hutt., var. murriensis, nov. 
Nanina monticola , Hutt., J. A. S. B., vii, 1838, p. 215 (North-Western Himalayas). 
Helix labiata, Pfr., P. Z. S., 1845, p. 65 (Loc. — ? — ) 
Both species are recorded and figured in the “ Conchologia Indica” as distinct, and I think 
very possibly the two forms there given may prove separable. Unfortunately, typical N. 
monticola is typical N. labiata , as figured 1. c., pi. xxvii, fig. 5. This I am able to prove by 
a fine series of typical N. monticola, presented years ago by Captain Hutton to the 
Asiatic Society, and now in the Indian Museum. Theobald correctly unites the two species in 
Ids catalogue, though I consider him mistaken in also uniting Beeve’s II. convexa. The form 
found by Dr. Stoliczka is near the much rarer one figured in the “ Conchologia Indica,” 
pi. lii, fig. 3, as H. monticola, and may prove distinct ; the Murree specimen differs indeed, even 
more markedly than the one there figured, in the characters which separate it from the type 
