Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/274

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Dimensions.

inches.
Length of skull from praemaxillary symphysis to occipital crest 33.0
From praemaxillary symphysis to (broken) articular end of tympanic bone 37.0
From praemaxillary symphysis to posterior limit of (anterior) nasal bones 14.0
From praemaxillary symphysis to point of Cuvier's large nasals 10.0
From praemaxillary symphysis to end of their median suture 19.0
Length of crotaphite foramen 06.0
Breadth of crotaphite foramen, about 06.0
Breadth of forehead between orbits 07.0
Breadth of snout at second tooth 03.1
Breadth at middle of dentary series 05.6
Breadth at hindmost tooth 10.2
Breadth of occiput 7.5x2 15.0
Height of occiput 07.3
Length of alveolar series (left side) 23.4
From praemaxillary symphysis to the anterior palatine foramen 01.9
From praemaxillary symphysis to palato-maxillary foramen 21.0

EXPLANATION OF PLATE IX.

Fig. 1. Under surface of skull of Steneosaurus Manselii.

a. Anterior palatine foramen. b. Praemaxillary -maxillary suture. c. Anterior extremity of pterygo-maxillary foramen. d. Basisphenoid.

2. Upper surface of skull.

a. The triangular bones corresponding to those lettered a a in Cuvier's figure of upper surface of snout of Gavial tete a museau plus court, b. The nasals. c. Their anterior termination in the nostril. d. The orbit. e. Parietal crest.

5. Note on some Teeth associated with Two Fragments of a Jaw from Kimmeridge Bay. By J. W. Hulke, Esq., F.R.S., F.G.S.

Amongst many other Kimmeridge fossils which Mr. J. C. Mansel has intrusted to me for examination are two pieces of a long, slender snout, not unlike that of a long -beaked Ichthyosaurus, but too fragmentary and crushed to allow of their certain identification.

The teeth differ from those of all the fossil fish and reptiles in the British Museum with which I have been able to compare them. They are peculiar in the great development of the cementum, which gives the fang the appearance of being inserted in a bulbous sheath. The base of the tooth resembles a little bulb, from the top of which a slightly curved, cylindrical, conical, and polished crown protrudes. The average length of the teeth is nearly 5-1/2 lines (English), of which about 3′″ belong to the neck and crown. The diameter of the neck and of the neighbouring part of the crown is about 1-1/6′″, while that of the bulbous fang reaches 2-1/6′″. The crowns are dark brown, polished, and smooth, and their transverse section is circular. They are composed of a simple tubular