OF HYPSILOPHODOX FOXII. 
1039 
in front, where, as mentioned by Huxley in a description of Mr. Fox’s type skull, it 
is wrinkled.* 
In both this and my skull, No. 110, the extreme end of the snout is missing, so 
that the actual anterior termination of the prsemaxillse is not certainly known. From 
each end of the body of the prsemaxilla a strong process ascends in the snout. Of these 
the median or anterior process, flattened, three-sided, tapering upwards to a point, 
ascends, closely applied to its fellow, between the mesial margins of the nasals for 
about one-third of the length of the snout (Plate 71, fig. 2*), forming with the 
descending narial process of the nasal lately described the internarial septum. The 
external or posterior prsemaxillary process (f in same fig.), wider, flatter, and longer 
than the anterior, intercalated between the maxilla and the nasal, curves upwards 
and backwards, resting in a groove in the anterior border of the maxilla, but not 
united to this by serrated suture. The dentigerous border in a space of 20 millims. 
in my skull, No. 110, contains in separate sockets five teeth, the same number as in 
Mr. Fox’s type skull. Since in both the extremity of the snout is abraded, it is just 
possible that • one additional tooth may have been present, although I do not think 
this probable ; or the ends of the praemaxillse may have been bent downwards in the 
form of a beak as Professor Huxley suggests.! 
Maxilla (mx.) (Plate 71, figs. 1, 2).—A large bone of rudely subtriangular out¬ 
line. The anterior border, convexly curved, is grooved on its outer surface for the 
reception of the external ascending process of the prsemaxilla, as was mentioned in 
connexion with the description of this bone. In my skull, No. 110, this border rises 
to a maximum height of 30 millims. above the dentigerous margin at the second molar 
tooth, making here an obtuse angle with the upper border which from this point 
curves gently downwards to a distance of 15 millims. above the last tooth. The 
nearly straight dentigerous border contains in a space of 43 millims. an unbroken 
series of eleven teeth, one more than in Mr. Fox’s type skull. 
In advance of the dentigerous portion of the maxilla a thin tongue-like plate formed 
by the convergence of the upper and the lower border is prolonged upon the deep 
surface of the body of the prsemaxilla, nearly if not quite reaching the anterior border 
of this latter. The upper margin of this tongue-like process of the maxilla must be in 
very close proximity to the lower and outer margin of the external nostril. Behind 
the hindmost tooth the maxilla narrows abruptly, and it sends backwards a stout 
three-sided process to which the jugal is united (Plate 71, fig. 1). Throughout nearly 
its whole length the outer surface of the maxilla, nearly in the level of the tooth- 
roots, is pierced by a series of conspicuous foramina as in Igaanodon Brest toichv, 
Megalosaurus, and Teratosaurus. 
The quadrate (Plate 71, figs. 3, 4; Plate 72, fig. l), a large, stout bone, is antero- 
posteriorly compressed near its articular ends and laterally flattened intermediately. 
* Huxley, ibid, 
t Huxley, loc . supra cit . 
6 R 
MDCCCLXXXII. 
