A. E. Verrill— North American Cephalopods. 205 
erful beak, 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 XV, 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, 70™ 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 
slight notch at its base. The anterior edges of the ale 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 ale, 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 
of the ale. The lamina of the mentum is short and strongly emar- 
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 lamin, is lined with a rather firm, somewhat chitinous 
or parchment-like membrane,* having its surface covered with strong, 
acute, recurved, yellowish teeth, apparently chitimous 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 
arranged 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 XVIa, 
fig. 5) occur in large numbers on the thinner extension of this mem- 
brane, which everywhere lines the mouth and pharynx. 
* Tn my first examination of this species, this tooth-bearing membrane was found, 
like the surrounding 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 mistal 
was corrected in the American Journal of Science, vol. xii, p. 236, 1876. 
