LOWER LIAS 
7 
those of the Liassic ocean, seem to have swarmed with carnivorous Enaliosaiirs. 
If the Dinosauria were ovo-viviparous, and produced but few young at a birth, 
the remains from the lower Lias figured in Tab. Ill might be those of a foetus 
borne by a gravid Scelidosaur to sea during an occasional excursion, and which by 
some casualty had there perished, and become imbedded, with her progeny, in the 
muddy bottom of the old Liassic ocean. I have not, however, been able to 
obtain precise evidence of the proximity of the small bones above described with 
any of the larger ones attributed to the Scelidosam'us, and bones of more than 
one small individual might have been expected to occur in juxtaposition if they 
had perished before birth. The analogy of the crocodile, moreover, would lead us 
to expect that the newly excluded or newly born Scelidosaur would be of smaller 
size than the individual indicated by the bones in Tab. III. 
The mull Tabs. IV, V, VI. 
The foregoing indications of a Dinosaur in the lower Lias excited speculation 
as to whether it had been herbivorous, like the Iguanodon of the newer Mezozoic 
beds, or carnivorous, like the Megalosaur, which has been traced from Wealden 
down to the great Oolite.” The structure of the femur pointed the former way, 
but the proof which the dentition only could give was wanting. 
The persevering encouragement afforded by Mr. Harrison to the workmen in 
the Lias quarries has, however, been rewarded by the acquisition of the fine 
specimen of a skull which forms the subject of Tabs. IV, V, and VI. 
The teeth, in their close-set, thecodont implantation, relative size to the jaw, 
degree of expansion, and general shape of the crown, resemble those ascribed to 
the Hylceosaurus (p. 21, tab. viii, figs. I — 3, ‘Monograph on Wealden Reptilia,’ 
1857) ; but the crown presents the median longitudinal prominence and marginal 
serrations which bring it closer to the Iguanodont pattern ; and, in the degree in 
which they depart therefrom, they still more closely resemble the teeth of the 
Echinodo7i from the Purbeck,* which may prove to be a small kind, or young, of 
a Dinosaur. They, how^ever, present different proportions. 
Referring, therefore, the skull in question to the Dinosaurian order, it sup- 
plies most acceptable information as to the cranial structure of that group, which 
no previous example from Oolitic and Wealden beds has been sufficiently perfect 
to impart. 
Of Iguanodon, Megalosaiirus, and Hylceosaurus, portions of lowmr jaw, and 
mere fragmentary bits of the upper jaw, palate, and basis cranii, are all that have 
hitherto come to light. But the present specimen is the entire skull, w'anting 
only the fore end of the upper and lower jaws. 
* ‘ Monograph on the Fossil Lacertian Reptiles of the Parbeck Limestones,’ p. 35, 1858. 
