84 ZOOLOGY. 
genus seems to be confined to the rivers of North America. Rafinesque’s 
generic name Jeptoxis was published two years before Say’s Anculosa. 
Some atithors suppose the former to be a genus of Physide, but the 
question is settled by some manuscript drawings of the former author, which 
represent the shell, tentacles, and operculum of Anculosa. 
Melanopsis is allied to Anculosa, and the species seem to be confined to 
Europe. It is probable that the few described species of European Melania 
belong in reality to Melanopsis. 
Say’s Melania armigera (and also Lea’s DL. duttonana and I. Catenoides), 
belongs to Rafinesque’s genus Plewrocera, in which there is a short straight 
canal anteriorly, and when this canal is jonetiened as in Fusus, the genus 
Lo of Lea is the result. Strepoma of Rafinesque (or Ceriphasia of Swainson) 
are slightly different forms, in which the aperture and the vertical plane 
formed by the anterior portion of the whirls, bear some resemblance to the 
same parts in Cerithium telescopium. 
Fusus fluvialis of Say is the type of Lo, isd as it would be an anomaly 
to find a genus so decidedly marine as Fusus inhabiting fresh waters, it 
becomes a matter of interest to know the animal of the American shell. This 
was observed in 1841, in its native waters in Holston, Powel’s, and Clinch 
rivers, in eastern Tennessee, by Halderman, who made a drawing of the living 
animal. Its characters and habits are not those of Fesus, but of Melania 
proper, as distinguished from Leptoxis; for although it inhabits the rapids 
as well as quiet water, in both cases it avoids the current by seeking shelter 
beneath shelving rocks, or in hollows or crevices in them. The head is 
large, and with the tentacles much exposed; the foot is as large as in 
Melania; the coloration is the same (black lines upon an orange ground); 
the operculum is subspiral as in Melania, the mantle extends into the canal of 
the shell, but does not form a closed siphon ; the vent is upon the right side; 
the mouth is a longitudinal slit; the eyes (which are sensitive to the light) 
are upon a short enlargement of the outer base of the tentacles, which may 
be a little longer than in Melania, and they are not visibly annulated. 
It differs from Fusus, and resembles Melania in living upon vegetable food ; 
and it moves along in a sluggish manner, moving the head from side to side 
upon the bottom. Jo spimosa and J. nlite are merely varieties of J. 
jiuwialis. The spinose individuals are much the most abundant, although 
the species is rare when compared with various species of Melanias 
Quoy and Gaimard, to whom the science of Malacology is indebted for a 
knowledge of the animals of many shells, have figured a number of species 
as belonging to Melania, the shells of which cannot be distinguished from 
those of that genus, whilst in the figures the mantle is represented as 
scolloped. Similar species were drawn in the course of the United States 
Exploring Expedition. These species must be placed in the family 
Cerithiidee. 
Fam. 2. Cerithiide. The genus Cerithiwm (pl. 75, jigs. 105-109) are 
remarkable for the great number of species both recent and fossil (tertiary) 
which it contains. The animal has the general character of Melania, except 
that the mantle is scolloped. 
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