PROF. OWEN ON NEW AND RARE CEPHALOPODA. 151 
mandible. The apophysis is strengthened on each side by a broad ridge or rising, g, 
extending longitudinally to the terminal apex. 
The muscular masses inserted into the mandibular apophyses are of a very dense 
tissue. The hinder fascicles open, the fore ones close, the beak. The outer and inner 
plates of the lower uncus recede in a less degree than those of the upper one; both 
are occupied by the condensed or tendinous modification of the mandibular muscular 
mass. 
A thick fleshy inner lip, fig. 2, 2, of a circular or sphincteric shape, immediately sur- 
rounds or inyests the mandibles: it is reflected from the base of the rostral part of the 
upper mandible at a greater distance (about double) than from that of the lower mandible 
(as shown in the section fig. 1, Pl. XX XI). The free anterior border of this lip is coarsely 
notched or divided into lobes, answering to the finer and more numerous marginal plice 
present there in most of the smaller forms of Dibranchiates. The outer lip is attached 
by eight fraena radiating from the outer side of the inner lip to the bases of the eight 
ordinary arms. Hach freenum sends off from the middle of its free margin a process 
which is fimbriate (Pl. XX XI. fig. 1, 7, 7), but does not develop any suckers. 
The lingual apparatus consists of the tongue proper and the rasp or “radule ;” to 
which are added a pair of “faucial folds” bearing on their inner surface small but 
distinctly visible horny denticles. The tongue proper (ib. fig. 1,7) is partially divided 
into two lobes, into the contracted base of which is inserted a slender “ retractor 
lingue ” muscle, f. The “radule,” &, encasing the third lobe of the lingual apparatus 
with its horny plate, bears on the upper and fore part thereof seven longitudinal rows 
of fine recurved spines. The faucial folds, /, 7, are continued from the sides of the base 
of the radular lobe and from the covering of the lingual salivary glands, m, as far back 
as the beginning of the cesophagus, n. Each fold is 24 inches in length, and 7 lines in 
breadth at the dentigerous part, behind which they gradually narrow to their cesopha- 
geal termination. ‘The horny armature is on the inner surface of the broader anterior 
portions of the folds; the spinules are slightly recurved, and affect, though less regularly 
than on the radule, a longitudinal disposition. 
The lingual salivary glands are compressed, parial, in close contact. ‘Their vertical 
extent is about one third of their length. They are convex and thick posteriorly, m, 
becoming flattened and contracting as they advance to send off each their duct, which 
opens into the cleft between the faucial fold and radule (as indicated by the bristles). 
The esophagus, , has a thick muscular and longitudinally plicate epithelial tunic ; 
the diameter of the contracted tube is half an inch’. 
The systemic ventricle (Prep. no. 963, Hunterian Physiological Series; Pl. XXXII. 
fic. 6) presents the same rhomboidal figure is in Onychoteuthis raptor (Pl. XXIX. 
fig. 4,9), with a similar relative position of the valvular terminations of the branchial 
1 A reduced cut of the subject of fig. 1 is given (fig. 225), and a general notice without details, in p, 621 of 
my ‘ Lectures on the Comparative Anatomy and Physiology of the Invertebrate Animals,’ 8vo, 1855. 
