A. j E Verrill — North American Cephalopods. 
289 
Sthenotenthis Bartramii Verrill ('continued). 
Sthenoteuthis Bartramii Verrill, this volume, p. 223, Feb., 1880; Amer. Journ. 
Sci., xix, p. 289, Apr., 1880. 
Ommatostrephes Bartramii Steenstrup, Oversigt Kongl. D. Vidensk. Selsk. For- 
handl., 1880, (received Aug.), auth. sep. copy, p. 9, fig. 2, p. 11. fig. 3, p. 19. 
Body cylindrical, elongated, slender, tapering but little in front of 
the fin ; anterior edge of mantle with a very slight, median dorsal 
angle. Caudal fin short and transversely rhomboidal, with the outer 
angles acute, posterior angle obtuse, and the front edges rounded 
and projecting forward beyond the insertion. Length of fin (from 
insertion) to its breadth, as 1 : 2 ; length of fin to mantle, as 1 : 2 ‘80, 
in a young female specimen with the body 3’25 inches long. Head 
short, as broad as the body ; eye-opening angular, higher than long, 
with a narrow oblique sinus. Nuchal trills nearly as in O. illecebrosa , 
consisting of a low, transverse, undulated ridge extending around both 
sides to the dorsal line, and with three raised longitudinal mem- 
branes on each side. Siphon large, sunken in a deep pit ; anterior 
border of the pit with a series of 6 to 12 or more (variable v r ith age), 
small and short furrows, which extend inward only a short distance 
from the edge. Arms rather short, not very unequal ; the dorsal 
ones are a little the shortest and smallest ; the third pair are the 
longest, the second and fourth pairs are intermediate in length, and 
nearly equal ; the arms of the second pair are furnished with a well- 
developed membrane along the lower outer angle, and with a thin 
marginal membrane of moderate width along the inner angles, out- 
side the suckers, that on the low’er side extending beyond the 
suckers. Those of the third pair are compressed, with a well-devel- 
oped membranous keel on the median outer edge, beyond the basal 
portion ; on the lower inner angle there is a broad, thin, marginal mem- 
brane, extending beyond the suckers, and a narrow one on the upper 
side ; the dorsal and ventral arms have narrow marginal membranes. 
Suckers of the dorsal and lateral arms furnished with horny rings 
which have the edge divided into small, acute-triangular teeth, 
largest on the outer side ; on the ventral arms the suckers are 
smaller, those on the proximal half of the arm having smooth-edged 
rings, while those on the distal portion are sharply toothed on the 
outer edge. Tentacular arms slender and moderately elongated, 
with distinctly broader clubs, which are keeled on the back side and 
furnished with a thin marginal membrane on each edge. The suckers 
consist of two median alternating rows of larger oblique, dentate 
suckers, of which seven to nine in each row are decidedly largest ; 
