466 



Description of Camptoceras. 



as in Ancylus, slow, and it adheres rather firmly to smooth surfaces. 

 Camptoceras affords a beautiful confirmation of the correctness of the 

 views of those Naturalists, who, deciding that the resemblance of Ancy- 

 lus to Patella was analogical, and not one of affinity, and placing it 

 among the Lymnaeadae, with reference to the characters of the animal, 

 separated it from the other Patelli form shells with which it was for- 

 merly associated. The analogies of Camptoceras have reference to 

 Scalaria among the Turbinidee, and to Vermetus among the Tubuli- 

 branchia. Occasionally a continuous varix, formed by the lip of a 

 former aperture, adds to the resemblance to Scalaria; but this varix 

 does not adhere, nor extend, as in that genus, to the preceding whorl. 



The animal adheres, under water, to the decaying stems of a long 

 reedy grass in a single piece of deep water, evidently forming part of 

 an ancient channel of the river, in the wide alluvial bed of the Ram- 

 gunga, north of the station and race-course of Moradabad, in Rohii- 

 khund. It was discovered by J. F. Bacon, Esq. Bengal Medical 

 Service, in an excursion which we made, with the intention of profiting 

 by the discovery of the shell next to be described, and which was 

 obtained by drawing out water plants from a stream, and care- 

 fully examining their stems and roots. The first specimens taken I 

 pronounced, when on the ground, to be merely a distorted variety of a 

 young Lymnsea Chlamys, which occurs of a large size, though spa- 

 ringly, in the same water ; and the variety of Lymnaea Peregra, figured 

 as No. 101, see Plate XI. of Gray's edition of Turton's Manual, was 

 calculated to confirm the idem ; but the sinistrorse volutions, and an 

 examination of the animal, and its habitation under a lens, quickly dis- 

 pelled the idea ; and an abundant supply was obtained by us in a few 

 morning excursions to the same spot. Other similar bodies of water, 

 one of them parallel to this favored one, and not distant from it one 

 hundred yards, failed to present us with specimens of the new genus. 

 We considered the discovery the more fortunate, as it was our intention 

 to visit another water, and the accident of finding the place of our 

 intended search occupied by travellers was the sole cause of our exa- 

 mination of the spot which afforded us so much satisfaction. We 

 here also re-discovered the new Trochiform, Planorbis, which we had 

 taken at Bhimtal, and this shell was similarly deficient in the other 

 waters of the neighbourhood. 



Fam. — TURBINIDiE. 

 Sub-Fam. — MELANIANiE. 

 Sub-genus.— TRICULA, Nobis. 



