3 
resemble any of thè East coast species closely enough to require a coraparison. 
It has a little thè aspect of a Campeloma, in some of its characters. 
Margarita vorticifera, n. s. PI. II, fig. 4, a, b. 
Shell depresseci, with 3 flattened, rapidly expandiug whorls, which bave a 
tendency, in old individuals, to overhang thè suture anterior to them. The 
upper surface is traversed by nunierous slender, slightly elevated, revolving 
threads, which are crossed by faint lines of grovvth, Outer edge of whorls sub- 
carinate. The basai surface is less flattened, but siniilarly sculptured, except 
that thè very wide and funnel-shaped umbilicus is destitute of revolving striae, 
and thè lines of growth are bere a little stronger. Aperture excessively oblique, 
with thè anterior angle much produced ; lips hardly thickened, and but slightly 
interrupted at thè junction with thè body whorl. Nacre, salraon-color ; exter- 
nal surface pinkish white, brilliantly pearly where eroded. Lat. of largest speci- 
men, 0.8.5 in.; alt. 0.5 in.; defl. 88°. 
Habitat : Iliuliuk Harbor, Captain’s Bay, Unalashka ; and larger specimens 
in thè Akutan Pass, from ten to sixty fathoms, on stony bottom. Not found 
in thè Shumagins. 
This species is more flattened than any species except M. helicina, which it 
somewhat resembles in form, though more carinated, and otherwise widely dif- 
fering in character. It is not allied to any West American species known to 
me, though it may bave relations with some Japanese form. It is a thin and 
light Shell. 
Volutopsis Beringi, Midd., var. regularis, Dall. PI. II, fig. 6. 
Shell of four whorls, obtusely fusiform, and with thè last whorl somewhat in- 
flated. Nucleus mammillated, whorls smooth, moderately convex, with a dis- 
tinct, though not channelled suture. Aperture eleven-seventeenths thè length 
of thè Shell, elongate, produced in front, with thè outer lip moderately thickened, 
and thè inner lip without callus. Canal almost straight ; short, narrow. Lon. 
1.15 in.; lat. 0.9 in.; defl. 65°. Color white, or light pinkish. 
Habitat; Unalashka, to thè Shumagins ; rare. This form may be a distinct 
species, but I bave preferred to indicate it as a variety, for thè present. It dif- 
fers from thè normal form in being smooth and regalar, without thè Inmps or 
irregular ribs which are common in thè V. Beringi ; it is sraaller in size, when 
adult, by one-half ; it is never of thè dark livid chestnut color which invariably 
characterizes V. Beringi. The outer lip is less patulous, thè canal proportion- 
ately narrower, and thè aperture shorter, compared with thè whole length of 
thè Shell. Moreover, thè specimens are remarkably uniform in their charac- 
ters, and thè V. Beringi, though very variable as a whole, is equally Constant 
in thè differential characters alluded to. I bave come to this conclusion only 
after a careful examination of over a hundred specimens of V. Beringi, and a 
good series of this form. The fornier is much more common in thè localities 
alluded to. 
In Dunker’s portion of thè Novitaies Concholo^icce,'pp. 1-7, 1858, and platea 
I and II, a number of species are described and figured as new, and stated to be 
from Sitka. The references to thè plates are erroneous throughout, as pointed 
