MOLLUSCA OF INDIA. 81 
noides secretes a calcareous poma or deciduous operculum every 
time that it retires into a state of torpor. The specimens in question 
had formed two or three successive pomata, one within the other, 
during the process of their desiccation. 
** In hopes of restoring their animation, I placed them upon some 
wet moss in a warm room. ‘Two of them proved to be past re- 
covery, but the animal of the third was seen through the trans- 
parent shell to be gradually enlarging in bulk by the absorption of 
moisture, and at the end of a week it finally reached the door of 
its dwelling, threw off the poma, and began to crawl. A morsel 
of boiled carrot was presented to it, which it greedily devoured, 
and speedily increased in health and vigour. I have now kept 
this interesting creature a twelvemonth, and have often been 
tempted to exclaim with Oken, ‘ What majesty is in a creeping 
snail; what reflection, what earnestness, what timidity, and yet at 
the same time confidence! surely a snail is an exalted symbol of 
mind slumbering deeply within itself.’ Since its revival my Na- 
nina has greatly increased in size, and has added half a volution to 
its shell, which now measures ;5, inch in diameter. Its favourite 
food is boiled carrots and raw lettuce-leaves. It generally remains 
quiet during the day, but crawls forth and shows considerable ac- 
tivity in the evening, and has never shown any inclination to hyber- 
nate or become torpid for a lengthened period. The shell of Nanina 
vitrinoides is brown, glossy, and pellucid, and in shape and colour 
closely resembles the shells of the European genus Zonites, from 
which, without examination of the animal, it seems to be generically 
undistinguishable. The animal, however, is very different, and is 
more allied to, though quite distinct from, that of the genus Vitrina. 
The foot when contracted is too large to be withdrawn into the 
shell, except after a considerable period of desiccation. When ex- 
panded, and at full stretch, the foot is remarkably long and narrow, 
measuring about 2 inches in length and + inch in breadth. The 
hinder extremity is abruptly truncate, surmounted by a short horn- 
like appendage, similar to that in the larvee of certain Lepidopterous 
genera. 
“ But the most peculiar character in the animal of Nanina is that 
of the two elongate pointed lobes or flaps which project from the 
margin of the mantle, one on each side of the mouth of the shell. 
These lobes possess a certain amount of lateral motion and a consi- 
derable power of retraction and expansion, but are always kept in 
close contact with the surface of the shell. 
“The animal is in the frequent habit of performing the following 
singular operation, which, as far as I am aware, has not before been 
noticed in any terrestrial mollusk. Crawling to the top of its prison 
(which consists of an inverted tumbler, with a small aperture for 
air), it suspends itself to the glass by the hinder half of “the foot, 
and twists the anterior part round so as to bring its lower surface 
into contact with the shell. By the great length and flexibility of 
the anterior half of the foot it is enabled to twist in a variety of 
directions, and thus to crawl as it were over every part of its own 
