A. M Verrill — North American Cephalopods. 391 



Plate XLV, pig. l-2d. Plate XLIX, fig. 1-1/ Plate LV, fig. l-\cl. 



Body elongated, tapering to an acute posterior end ; anterior edge 

 of mantle nearly even dorsally, with a slight median emargination ; lat- 

 eral angles well-marked, in line with the internal connective carti- 

 lage, which forms a long, simple, longitudinal ridge. Caudal fin 

 broad spear-shaped, broadest in advance of the middle ; the lateral 

 angles are well rounded; the tij) is very acute; the anterior lobes are 

 broadly rounded, projecting forward beyond the insertion. Head 

 large, short and broad ; eyes large, occupying most of the sides of 

 the head ; eye-lids well developed, thickened, with a narrow, oblique 

 sinus. Siphon large, in a deep groove, with two stout, dorsal bri- 

 dles; lateral connective cartilages large, long-ovate, posterior end 

 broadest. One olfactory crest on each side, behind the eye, in 

 the form of a low, longitudinal membrane; slight indications of 

 another, lower down ; a small, fleshy, flattened, projecting papilla 

 near the auditory opening. The outer buccal membrane has seven 

 distinct angles. Arms rather long and strong ; trapezoidal in sec- 

 tion. The dorsal arms are considerably shorter than the others ; 

 order of length is 1, 2, 4, 3 ; the 3d is but little longer than the 

 second pair; ventral arms decidedly more slender than the others. 



Ventral arms with four rows of denticulated suckers, those of the two 

 inner rows larger; lateral and dorsal arms with two marginal rows of 

 small suckers and two inner roAvs of larger incurved hooks, enclosed, 

 except at the sharp tips, in muscular sheaths, which have lateral basal 

 expansions and short pedicels (PI. LV, fig. lb). Tentacular arms* long 

 and strong, quadrangular ; in my specimen they reach back beyond 

 the base of the fin ; the club is large and broad, with a long, 

 narrow distal portion, having a strong dorsal keel ; in the middle are 

 two very large, curved hooks (fig. 1, la), the distal one smaller; 

 proximal to these there is a row of five smaller hooks, decreasing 

 proximally, and between these and the large hooks there is, on 

 one arm, a single small sucker ; on the other arm a single sucker 

 takes the place of the proximal hook, while an odd, small sucker 

 stands to one side of the row ; along the upper margin of the club 

 there is a broad band of small, denticulated suckers, on long ped- 

 icels, arranged in oblique, transverse rows of five or six ; this band 

 of suckers is interrupted opposite the large hooks ; beyond the hooks 



*The figure given (pi. XLIX, fig. 1,) of the somewhat injured tentacular club of 

 the type of Gheloieuthis rapax, represents the structure nearly correctly, but many of 

 the small suckers and tubercles on the arm, below the club, had been destroyed, the 

 edge above e' is injured, and of the large hooks (a, a') only the sheaths remain. 



