Cope.] 274 [Dee. 17, 
neural arch, are scarcely excavated above for the neural canal. The dia- 
pophysis with stout inferior horizontal branch, which is capped by an 
extension of the articular catilage from the rim of the cup. Occipita 
crest elevated, sub-vertical. Quadrate broad below ; pit sunk between 
bounding ridges. 
Description. There is a great disproportion in the sizes of the cervical 
aud posterior dorsal vertebree ; the centra of the latter are rather more 
depressed than those of the former. They are similar in proportion to 
those of the Holeodi and shorter than those of the Hdestosaurt. The 
short axes of the articular faces are sub-vertical. The rudiment of zygos- 
phen is seen in the slight anterior prolongation of the roof of the neural 
canal. The keel of the hypapophysis of the atlas is short and obtuse. 
The greater part of the cranium is preserved. The supra-occipital keel 
is vertical and furnished at the summit with a plicate knob for the inser- 
tion of a Kigamentum nuchw. The thickness of the walls of the bone is 
pheus and the suture is a double squamosal 
not equal to that in H. cor 
?. ¢. with groove along the middle of the edge. The basisphenoid is but 
slightly keeled below, and is distally expanded into a horizontal plate on 
each side. The parietals are, as usual, confluent, and send off two light 
arches postero-laterally for union with the squamosal bone. Between 
their origins are two sub parallel ridges which disappear, the transverse 
section of the narrow part of the parietals being rounded. The lateral 
ridges within the temporal fossee are obsolete, while the convergent angles 
lg thin the temporal fossee are obsolete, while the vergent angles 
which bound the parietal table posteriorly are strongly marked: This 
table is nearly plane and the foramen partetule is large. The frontal is 
narrowed in front, and has an elevated keel along its anterior half. The 
olfactory groove is not much contracted behind, but is closed by the apex 
of the rugose area in front of the foramen parietale. 
The palatine bone is narrow and the external margin is very slight, the 
bases of the teeth being exposed in that direction. The inner margin is 
8, but not so as to be a vertical plate. The 
hinder part of the bone is flat and horizontal, with a long maxillary pro- 
cess. The pterygoid notch falls opposite the second tooth from behind, 
The whole number of teeth is eleven. : 
The jaws are represented by the greater part of all of the tooth-bearing 
portions. The maxillary bone is shallowly sulcate on the exterior face. 
Its proportions are quite similar to those of the H. coryphaus, but the teeth 
it supports are larger and fewer, There are none missing from the ex- 
tremities of the specimen, the whole number being ten; in ZH, corphy@us 
there are eleven. The crowns are incurved, faceted externally, and 
striate-grooved internally ; there are cutting edges on front and rear, 
both strongest near the apex ; the anterior continued to the base, the latter 
wanting on the basal third on median maxillaries. The anterior nareal 
expanse marks the fourth tooth from the premazillary suture. The 
premarillary bone is remarkable for its shortness and flatness at the 
extremity, this part being depressed and scarcely projecting at the lower 
margin in front of the anterior teeth. These as usual number four. 
much thickened downwards. 
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