494 A, E. Verrill— Catalogue of Marine Mollusea. 
marked sinus below the suture, in adult shells, and then a little ex- 
curved and thickened ; below this, broadly rounded, often somewhat 
expanded anteriorly and usually extending somewhat beyond the end 
of the columella; canal short, obliquely truncated, not very wide; 
columella-lip regularly arched above the middle, not excavated; col- 
umella smooth, nearly straight in the middle, a little receding, thin 
and evenly rounded at the end; plications quite obsolete, or very 
nearly so. Operculum irregularly elliptical, obliquely narrowed at 
the right end, its nucleus excentric, nearest the broad end, and not 
far from the edge. 
A female, of the ordinary size, from off Cape Sable, N. S., is 43™™ 
long; breadth, 25"™; body-whorl, to end of columella, 30"; its 
breadth, 20"; length of aperture, 23"; its breadth, 13™™; length 
of operculum, 11°5""; breadth, 9"™™. 
Var. patulum (G. O. Sars). 
Op. cit., p. 260, pl. 25, fig. 2. 
From Murray Bay, mouth of the St. Lawrence River, Principal 
Dawson has sent me specimens, of a peculiar, rather small form, be- 
longing, apparently, to this species. The aperture is unusually broad, 
with the lip expanded and patulous anteriorly, projecting decidedly 
beyond the columella. The surface is eroded, but was nearly smooth, 
without ribs, and with fine wavy, unequal, spiral lines, mostly indis- 
tinct; one specimen has several larger, distant, raised spiral lines. 
The color is dark brownish ; inside of aperture purplish or livid brown, 
This species appears to be cireumpolar. It is common in Davis 
Straits and on the coasts of Greenland, Spitzbergen, Nova Zembla, Ice- 
land, Finmark, Lapland, etc. Fossil in the Post-pliocene of Canada. 
Morch, in adopting Grintandicum for this species, simply took up a 
part of the polynomial name used by Chemnitz, which has no claims 
to priority under the ordinary rules of binomial nomenclature. Stimp- 
son, therefore, very properly rejected that name, as applied to this 
Species, and adopted the first distinctive binomial name given to it. 
Jeffreys has followed Mérch in using B. Grénlandicum, and various 
other European writers have followed the same usage, apparently 
without sufficient reason. This has given rise to much confusion, 
because Grénlandicum has been extensively used for a very different 
species by Hancock, Reeve, Stimpson, and various other writers. 
The Tritoniwn Terre-Nove (Mirch) has been referred to B. Tot- 
tenti by Jeffreys, but Mérch himself suggested that it might be a 
