PALUDOMUS. 
Puate I. 
Genus PaLtupomus, Swainson. 
Testa ovata, subventricosa, spird brevi, nunc depressi, nunc 
easertd, columella subeacavatd, latiusculd, pland, basi 
integra, rotundaté ; apertura ampld, subsemicirculart, 
superné paululum canaliculaté, labro simplici. Epi- 
dermis olivacea, fusca atrave. Animal fluviatile, oper- 
culo corneo, subtrigono-ovato, concentricé striato. 
Shell ovate, somewhat ventricose, spire short, sometimes 
depressed, sometimes exserted, columella a little 
excavated, rather broad, flat, entire at the base, 
rounded; aperture large, somewhat semicircular, 
slightly channelled at the upper part, lip simple. 
Epidermis olive, brown or black. Animal fluviatile, 
with a horny subtriangularly ovate, concentrically 
striated operculum. 
The genus Paludomus was founded by Mr. Swainson 
in his ‘'[reatise of Malacology’, forming Vol. 123 of 
Lardner’s Cabinet Cyclopedia, for the sake of distin- 
guishing an ovate oblong form of Melania brought from 
Ceylon by Dr. Sibbald, and of which three species were 
figured by Mr. Griffith in his edition of Cuvier’s Animal 
Kingdom. The genus has, however, remained in com- 
parative obscurity from the want of any species being 
known of sufficiently typical character to render it appre- 
ciated. That desideratum has now been supplied by the 
zeal of Mr. George Gardner of the Royal Botanic Gardens 
of Ceylon, a gentleman much attached to Natural History, 
and already known to the scientific world by his interesting 
botanical researches and ‘ Travels in the Interior of Brazil.’ 
Having already figured the Paludomus loricatus in anti- 
cipation of the genus (Hlem. Conch. pl. xviii. f. 100) whilst 
only one or two other species approaching Melania were 
known, it has been satisfactory to receive such an impor- 
tant typical addition to the group as that afforded by the 
present series; more especially by the P. loricatus, Gard- 
neri, Tennantii, undatus, pictus, and funiculatus, all of 
which are characterized by an oval Nerite-like form which 
fully entitles them to the generic distinction less signifi- 
cantly awarded by Mr. Swainson to the species verging 
on Melania, and of more doubtful importance. 
Of the following species, thirteen are from Ceylon, two 
from the Himalayan district of India, and one from Point 
Palmas, Sumatra; and to complete the monograph of the 
genus may be added Melania Stephanus, Benson, Journ. 
Asiat. Soc. Calcutta, vol. v. p. 747, figured by Philippi in 
Abb. und Besch. Conch. pl.1. f.5,6, under the name Melania 
coronata, Von dem Busch.; and, apparently belonging to 
this genus, two species figured by the same author as 
follows :—WMelania obesa, Philippi, 1. c. pl. iv. f. 3, from 
New Holland; and Melania Gruneri, Jonas, Phil. 1. c. 
pl. iv. f. 2, from Grenada, but the localities of these are 
doubtful. Lastly may be added a species named (but 
not described) by Mr. Gray, Melania retusa, Griff. Cuv. 
An. King. pl. 14. f. 9. which I have not succeeded in 
identifying. I am not aware that the genus exists in any 
of the streams of North America, but it may be said to 
be represented by Mr. Say’s Anculosa, which appears to 
be as peculiar to the Transatlantic district as Paludomus is 
| to the Ceylonese. 
Like all fresh-water shells the Paludomi are of a dark 
sombre colour, always more or less eroded at the apex, 
the Nerite-shaped species exhibit, however, a very charac- 
teristic waved pattern interiorly in an incipient stage of 
growth, which in a more advanced state is entirely over- 
laid by a deposit of colowless matter, when they are 
further distinguished by a rich chocolate-brown tint of 
colouring on the columella and edge of the aperture. 
The animal is probably little more than a modified condi- 
tion of the Melania, being similar in habit and having the 
same black horny operculum of a more triangular form. 
Species 1. (Fig. a, 6, c. Mus. Cuming.) 
PaLupomts toricatus. Pal. testd obovata, spira vi 
eusertd, anfractibus superné leviter angulato-depressis, 
liris squamato-nodosis creberrimé spiraliter cingulatis ; 
apertura ampli; nigerrimo-fuscd, intus alba; colu- 
mellé et aperture limbo purpureo-fuscis. 
THE MAILED Patupomus. Shell obovate, spire scarcely 
exserted, whorls slightly angularly depressed round 
the upper part, spirally encircled with close-set squa- 
mate ridges; aperture large; very black brown, 
interior white, columella and edge of the lip purple- 
brown. 
Hab. Yn yapids flowing from Adam’s Peak, Ceylon; 
Gardner. 
The entire surface of this species is closely spirally 
encircled with noduled ridges, in which particular it differs 
from all the rest. The nodules appear to have been ori- 
ginally represented by scales which have become closed up. 
July, 1847. 
