A. E. Verrill — JSforth American Cephalopods. 205 



erfnl heak, looking something like that of a parrot or hawk, except 

 that the upper jaw shuts into the lower, instead of the reverse, as in 

 birds. The color is dark brown, becoming almost black toward the 

 tip, where its substance is thicker and firmer and smoothly polished 

 externally. The upper jaw (Plate XY, fig. 1), in 1875, measured 97"""' 

 in total length ; 25'""' in transverse breadth ; and 66"^™ in breadth or 

 height. The lower jaw (fig. 2) was 76™"' long, 7o™'" transversely, and 

 67™"' broad, vertically. It was larger when first received, but has 

 subsequently shrunk considerably more, in alcohol. 



The upper mandible has the rostrum strong, convex, acute, and 

 curved considerably forward, with concave cutting edges, and a 

 slisrht notch at its base. The anterior edges of the alae are irregular 

 and uneven. The palatine lamina is broad and thin. 



The lower mandible has the rostrum stouter and less curved, the tip 

 acute, with a distinct notch just below the tip, the cutting edges nearly 

 straight, and with a moderately deep and rather narrow notch at its 

 base ; a ridge runs backward, from near the tip, in a curved line, 

 circumscribing a more flattened area, on which are grooves and ridges 

 parallel with the notch. Beyond the notch, on the anterior edges of 

 the aire, there is, on each side, a broad, low, obtuse lobe or tooth, 

 beyond which the edge is even and slightly concave, to near the end 

 ofthealfe. The lamina of the mentum is short and strongly eraar- 

 ginate in the median line. Detailed measurements of the parts are 

 given in the table of measurements on a subsequent page. 



The roof of the mouth, or palate, between the anterior portions of 

 the palatine laminae, is lined with a rather firm, somewhat chitinous 

 or parchment-like membrane,* having its surface covered with strong, 

 aciite, recurved, yellowish teeth, apparently chitinous in nature, 

 attached by broad, oval or roundish, flattened bases (Plate XVI, fig. 

 1 ; XVIa, fig. 4). These teeth are mostly curved, and very unequal 

 in size and form, the various sizes being intermingled. They are 

 ari'anged in irregular quincunx, in many indefinite rows. Many 

 irregular, roundish, rough, white, stony granules are also attached 

 to this membrane, among the teeth. Similar granules (Plate XVI«, 

 fig. 5) occur in large numbers on the thinner extension of this mem- 

 brane, which everywhere lines the mouth and pharynx. 



* In my first examination of this species, this tooth-bearing membrane was found, 

 like the siirronnding parts, much mutilated, and was mistaken for the odontophore, 

 and described and figured as such. The real odontophore was discovered later, loose 

 in another can, with other fragments of the same specimen, and this serious mistake 

 was corrected in the American Journal of Science, vol. xii, p. 236, 1876, 



