new Species of Marine Shells. 181 
OzssERvaTIONs. Half a dozen specimens of this cu- 
rious little shell were procured from codfish, taken last 
January off Provincetown, in about thirty fathoms water. . 
It is very distinct from any species I have ever seen de- 
scribed, in the singular formation of the body whorl, the 
summit of which shews no trace of any spire, the lip : 
arising from it much the same as it does in the young of 
Cypr&éa. The aperture is exceedingly dilated toward 
the base, by the arcuation of the columella, and the very 
strong outward curvature of the lip; the base is very 
slightly effuse... The brownish tinge on the inferior por- 
tion of the body, seems to be owing to a very slight de- 
posit of extraneous matter. 
Burta Gourpu. : 
Plate IV. fig. 6. 
parva, ovata, convolutá, fragili, albá, transversim tenué 
striata, spirà depressi, imperforatà, interdum prominulà, anfractibus — 
quatuor, superné rotundatis, suturis impressis, Siren — angustà, 
versus basim dilatatà, columella arcuata. 
Description. -Shell small, ovate, thin, brittle, shin- 
ing, white, rather opaque, convolute, composed of four 
volutions, rounded at their upper edges, and having the 
sutures strongly defined, the last whorl nearly envel- 
oping all: the others; and covered with numeroüs, fine, 
impressed, transverse strie ; spire depressed, discoidal, 
sometimes slightly mammillated, incremental striæ hardly 
discernible ; the lower extremity of the shell rather nar- 
rower than the upper. The aperture is narrow supe- 
riorly, and abruptly dilated toward the base by the ar- 
*. uf aut 
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