The nasals are rather broad; they send processes into the anterior narial opening, which tend to divide it, but this division was probably not complete. The limits of the prefrontals and lachrymals are so obscure as to preclude description.
The frontals are long and very narrow, though wider than in the alligator. They are smooth and flat, exhibiting no concavity on top. They expand considerably at the posterior part of the orbit, at the sutures with the post-frontals. These bones are long, stout, and curved very strongly outwards.
The mastoids are of remarkable size; they project far backward along the tympanic, and encroach largely upon the occipital region. It is partly owing to this that the occiput is so high.
The parietals are short, and very narrow between the temporal orifices, behind these they expand considerably. The orbits are large and of irregular shape.
The malar is long and rather slender.
Measurements.
| M. | |
| Length from occipital border to end of muzzle | ·455 |
| Breadth of cranium at postorbital angles | ·0935 |
| Breadth of cranium between temporal orifices | ·019 |
| Breadth of forehead between orbits | ·036 |
| Breadth of temporal orifices | ·037 |
| Fore-and-aft diameter of the same | ·038 |
| Fore-and-aft diameter of the orbits | ·073 |
| Length of face in advance of the orbits | ·3055 |
| Breadth of face outside of the fifth maxillary tooth | ·176 |
| Breadth of muzzle as formed by premaxillaries (about) | ·114 |
| Breadth of muzzle at notch for canine | ·093 |
| Length of premaxillaries to notch | ·080 |
| Estimated length of entire alveolar border | ·283 |
| Breadth of articular surface of quadrate | ·059 |
| Vertical height of occiput | ·124 |
| Vertical diameter of foramen magnum | ·016 |
| Transverse diameter of foramen magnum | ·025 |
| Vertical diameter of condyle | ·023 |
| Transverse diameter of condyle | ·028 |
| Length from palatine foramen to end of pterygoid | ·120 |
| Length of palatals | ·1295 |
| Length of palatine foramen | ·142 |
| Greatest breadth of palatine foramen | ·051 |
| Length of bony palate from incisive foramen to posterior nares | ·350 |
The mandible is long, rather shallow, but very thick. The symphysis is very long, extending as far as the seventh tooth. The chin is quite sharp, but becomes broad, as the rami diverge quite rapidly. The alveolar border is rounded and comparatively straight, the median enlargement of the dentary is in thickness rather than in height. The two rami diverge at an angle which is more open than in the true crocodiles, and less so than in the alligator. The mandibular foramen is smaller than in the latter genus, but corresponds with it in position; it has its long diameter parallel with, and not oblique to, the alveolus. The mandibular fossa is extremely large and deep. The splenial is long and stout, ends obtusely, and does not reach the symphysis. The articular cavity is broad from side to side, but rather shallow; it is not divided into two distinct facets as in the alligator. The post-glenoid process is very stout; it projects but slightly upwards, less so than in either crocodile or alligator. It has no median ridge as in the former genus, and is tuberous at the end.
The teeth are much like those of the upper jaw, but are somewhat sharper and more conical; they are not recurved, and have no distinct constriction, as is found in most of the recent species. There are about eighteen teeth to each ramus; the first is large and sharp, and is followed by two small ones and then by the canine. The remaining teeth do not exhibit any great differences of size.
Measurements.