A. E. Verrill — JSForth American Cephalopods. 231 



are very large, with the median more decidedly the largest, and the 

 one on each side of it is shorter as compared with the next ; six, on 

 the inner margin, are minnte, and these are connected, by one or two 

 somewhat larger ones, at each end of the inner border, Mitli the 

 larger series. 



The stumps of the tentacular-arms are flattened, oval, and smooth, 

 measuring about 10 by 18'"'", near the base; their length is about 

 28'='" (11 inches), which is doubtless less than half their original 

 length. 



The exposed parts of the jaws are black and polished ; the laminne 

 are reddish brown, with broad, thin, yelloAvish-white margins. The 

 upper mandible has a long sharp rostrum, with regularly curved cut- 

 ting edges, and a small, well-defined, V-shaped notch, from which a 

 short groove runs backward, beyond which there is a slight ridge ; 

 anterior edge of alse, beyond the notch, forming no distinct lobe or 

 tooth, but slightly convex, and irregularly crenulate ; posterior lateral 

 borders of alne with a broad sinus in the middle ; palatine lamina long 

 and thin, with sinuous posterior margins ; frontal lamina broad, ex- 

 tending well backward. 



The total length of the upper mandible is 42'"'" ; tip to posterior 

 end of frontal, 33""^'; to notch, 10"""; greatest breadth (or height), 

 from palatine to end of frontal, 30""" ; transvei'se breadth, across 

 frontal, 15'""'; transverse breadth, across anterior edges of alse, 8'"'". 



The lower mandible has a strongly incurved beak, with the cutting 

 edges rather suddenly incurved at about the pi-oximal third, and a 

 well-developed, broad, V-shaped notch at base, beyond which there is 

 a slightly prominent, broad tooth ; alie broad, the inner ends broader 

 than the middle, well-rounded ; mentum short, with a broad dorsal 

 emargination ; gular lamina short, the inner edges incurved. 



The total length of the lower mandible is 29'"'" ; tip of beak to end 

 of mentum, 10'"™; to ventral end of gular, 21'"'"; to bottom of notch, 

 11""" ; to inner ends of alae, 24'"'" ; breadth, from inner ends of alae to 

 mentum, 28™™; breadth of gular lamina, 17™'"; breadth of alae, 

 12-5'"™; greatest transverse breadth, across alae, 32™™; transverse 

 breadth, across anterior edges of alae, at teeth, 1 1'"™. 



These jaws agree pretty nearly, in form and size, with those of 0. 

 pterojms, figured by Steenstrup, but the latter have a deeper notch 

 in the upper mandible, with a more evident lobe beyond it, while the 

 lower mandible has a broader and less triangular notch. 



The buccal membrane is large, thin, prolonged into seven acute 

 angles or lobes, of which the upper is in the median plane, opposite 



