LIASSIC CROCODILES. 141 



The specimen figured is from the Lias of Wliitby, and is now in the British 

 Museum. 



Species — Teleosaitrus latifrons, Owen (Grocodilia, PI. 17). 



The proportions of the cranial and facial parts of the skull in Teleosmirus 

 Ghapinanni (PI. 15) are defined in the characters of the preceding species. In 

 Tel. latifrons the part of the skull anterior to the orbit includes three times the 

 length of the upper part of the cranium behind the fore part of the orbit. The 

 entire length of the skull in the present species is about three times its greatest 

 breadth, that is, taken across the back part of the temporal vacuities. In Tel. 

 Chapmanni five times that breadth are included in the total length of the skull. 

 Thus, in its general proportions Teleosaurus latifrons, like Tel. brevior, approaches 

 near to the Geoffroyan genus Steneosaurus , but the terminal, almost vertical ex- 

 ternal nostrils, the antorbital vacuities, with the relative slenderuess of the pro- 

 duced upper and under jaws, are strictly teleosaurian. 



The occipital surface, viewed from above, describes a more regular concave 

 curve than in Tel. Chapmanni or Tel. brevior, the frontal region between the orbits 

 is broader, both absolutely and relatively, to the skull's length, suggesting the 

 specific name. The parietal division of the temporal vacuities has been reduced 

 by long exercise of the muscular masses therein lodged to a ridge, the walls of 

 which diverge slightly at the fore part to give issue to the cerebral production 

 traversing the " foramen pineale." The mastoid and squamosal supports of the 

 tympanic joint are mai^ked respectively by the letters o and n, fig. 1. From the 

 squamosals, the sides of the skull converge with a gradual and gentle curve to the 

 maxillary elements of the upper jaw. The nasals terminate anteriorly, by their 

 usual pointed inter-union, at the middle of the skull's length. 



The form of the transverse section of this part is added to figure 2 (palatal 

 surface of skuU) ; also a similar section is shown, taken across the hinder-pointed 

 ends of the premaxillaries. In advance of these the premaxillaries are slightly con- 

 stricted laterally, but the fossil fails to give satisfactory indications of large inferior 

 canines as the cause. Anterior to these the premaxillaries expand, and so surround 

 the outer nostrils as to give them the almost vertical teleosaurian position. The 

 palatal surface of the mandible and two sections are shown in fig. 4, PL 17. 



The specimen above described and figured is from the oolite of Northamp- 

 tonshire. 



Species — Teleosaurus asthenodelrus, Owen. 

 If the cranium of this Saurian should correspond with the characters of the 



