474 
A. K. Verrill — Catalogue of Marine, Mollusca. 
A large example (sex unknown), measures, in length, 17 ,ul “; 
breadth, 7 - 5 mm ; length of body-whorl, ll - 5 m “'; its breadth, 6 •4 mm ; 
length of aperture, 9 lum ; its breadth, 3 ,m “. A specimen ascertained 
to be a male is 14'5 u,in long; breadth, 6*5 mm ; length of body-whorl 
and canal, 9'75 a ““ ; breadth of body-whorl, 6" 1 " 1 ; length of aperture, 
8""“ ; its breadth, 2 , 5 mm . 
This species ranges from Long Island Sound to Nova Scotia, but 
is less common northward. It is the most common species south of 
Cape Cod, in moderate depths (18 to 30 fathoms), where it is 
usually unaccompanied by any other species, and occurs of large 
size and typical form. We took it oft' (-ray Head, Martha’s Vine- 
yard, 18 to 29 fathoms, in 1871, 1880, 1881; oft' Block Island, 20 to 
28 fathoms, 1874, 1880; eastern end of Long Island Sound, 1874; 
Massachusetts Bay, 8 to 29 fathoms, 1873, 1877, 1878, 1879; Cape 
Cod Bay, and oft' Cape Cod, 15 to 34 fathoms, 1879; Casco Bay, 
1873; Eastport, Me., and Bay of Fundy, 10 to 50 fathoms, 1870, 
1872; Halifax harbor, 20 fathoms, and oft’ Halifax, 120 miles, 190 
fathoms, 1877 ; oft' Martha’s Vineyard, 104 miles, 368 fathoms, 1881. 
Messrs. Smith and Ilarger, on the “ Baclie,” in 1872, took it at 
various localities on George’s and Le Have Banks, in 25 to 60 
fathoms. 
Bela harpularia lias often been confounded with B. scalar is, B. 
cancellata , and other species. It differs widely from the former 
in the shape of the aperture and in the brevity of the canal; in 
the more sloping and obtuse shoulder; in the closer ribs; and in 
the finer and peculiarly waved spiral lines, which are finer near 
the shoulder. B. cancellata has a higher and more acute spire, 
ftexuous ribs, and coarser spiral sculpture, which becomes still 
coarser anteriorly, toward the canal. 
Defrancia Woodiana Moller, from Greenland, has been considered 
identical with this species by several authors. Moller’s description 
is of no value. I have seen no Greenland examples of B. harpularia , 
and as it becomes decidedly rarer to the northward, on our coast, its 
occurrence at Greenland seems to me doubtful. It becomes compara- 
tively rare in the Bay of Fundy and off Nova Scotia, where it is 
mostly replaced by B. cancellata , B. scalaris and other more arctic 
forms. A somewhat similar shell, which I have identified as B. 
Woodiana , occurs on the coast of Greenland, from whence I have 
specimens, and on the coast of Nova Scotia; this is probably the 
Greenland shell that has been mistaken for B. harpularia by various 
writers. 
