224 MELANIIDA. 
One or two exactly resemble M. Brot’s pl. 21, fig. 5—long. 313, 
diam. 11 mil.; the others have the last whorl more contracted, 
evenly rounded, instead of slightly subangulate—long. 314, 
diam. 10 mil. The largest long. 394, diam. 123? mil. They 
are all of a plain, uniform coloration, without any traces 
either of spots or bands. 
subvar. cochlidium. 
Melania cochlidium, Lea, P. Zool, S. 1850, Siquigor and Guimaras; Reeve, 
Sig. 27. 
3 Katchall ; coll. F. A. de Roepstorff, Esq. 
The infra-sutural ledge is less marked than in the above- 
quoted figures, but still quite distinct, especially near the aper- 
ture. 
var. pirenoidea, nov. 
2 [Camorta ? Nicobars] ; coll. F, A. de Roepstorff, Esq. 
A remarkable, ‘‘ Pirena-like,” strongly decollate and massive 
form, perhaps the origin of the observation in the voyage of the 
“ Novara ” of the finding of a species of Pirena at Katchall P 
One specimen of 4 whorls measures long. 30, diam. 12 mil., 
andis well represented by M. Brot’s pl. 21, fig. 16a, the apical 
whorls of course being left out of consideration ; the other of 
3 whorls, and the internal portion of a fourth has the last 
whorl more convex, with a slight infra-sutural shelf; long. 30, 
diam. 13 mil. M. Brot’s pl. 21, fig. 16, though smaller and with 
the last whorl more cylindrical, gives a very fair idea of it; 
both are of uniform coloration. 
2 Camorta? ; coll. F, A. de Roepstorff, Esq. 
One is.a quite young specimen of 7 whorls, slightly decollate, 
as in Brot’s pl. 21, fig. 17; the other of medium growth, has 
5 whorls remaiming, none of which show the apical sculpture 
as does the preceding. I have little hesitation in referring both 
of them to this variety as non-adult forms. 
subvar. perdecollata. 
2 Nicobars ; coll. F, A. de Roepstorif, Esq. 
