Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/129

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1870.]
HULKE—REPTILIAN FOSSILS FROM GOZO.
31

of two narrow slips, they meet the præmaxillæ opposite the interspace between the 11th and 12th teeth, counted from behind. For some distance above and below this spot, the widths of the nasals and of the ascending slips of the præmaxillæ are so nearly equal that the junction of the two pairs of bones is inconspicuous and may easily be overlooked.

The prefrontals form rather less than half of the inner border of the orbit, and they are marked by the groove already described. The lachrymals descend along the outer border of the nasals nearly as far again as the prefrontals.

The upper surface of the snout has been flattened by pressure. It is marked with a rather coarse longitudinal wrinkling. The borders of the snout are even behind the 8th tooth, but in front of this the prominence of the alveoli makes them slightly crenated.

The under surface of the skull has the common features of a crocodile's. The mesial borders of the palatine and pterygoid bones meet throughout their length. The posterior nares, wholly included within the posterior border of the connate pterygoid alæ, look backwards. The transverse diameter of their opening slightly exceeds the axial diameter. The pterygo-palatine foramina are long and narrow, their inner border is nearly straight, and their outer border is concave.

The occipital surface of the skull is nearly plane vertically, slightly convex transversely above the foramen magnum, and external to this slightly hollow.

The mandibular symphysis, with about 4" of both rami behind it, and nearly as much in front of it, remains attached to the under surface of the snout. The symphysis begins opposite the interspace between the 7th and 8th maxillary teeth, counted from behind. The splenial bones are included in it.

The teeth are subequal, conical, sharply pointed; when fully extruded slightly retrocurved, unequally compressed laterally, the outer surface more convex than the inner one, the compression increasing towards the apex of the crown, and forming here a back and front smooth edge. The hinder maxillary teeth are shorter, they taper less, and are more compressed than those in front. The fang is large, and it has a capacious, open pulp-cavity. The crown has a thick coat of enamel, which on the outer side of the tooth is marked by low longitudinal striæ, widely set near the base, and closer and finer near the apex; on the inner side it is extremely finely striated or, rather, wrinkled.

A label affixed to the fossil before it came under my hands, and when it was still nearly hidden in the matrix, showed that it had been referred to Melitosaurus champsoides, Owen. I have compared it with the type specimen of this species in the British Museum[1], and find that it agrees with this in the long mandibular symphysis, in the narrowness of the ascending processes of the præmaxillæ, and in the

  1. The terminal 13 inches of the maxillæ and mandible of a large crocodilian.