242 BRITISH FOSSIL REPTILES. 



far back as the nostril, ' Pferosawria,' PI. 1, fig. L In the Pterodacft/Jus crassirostris* , 

 (ib. fig. 2,) on the other hand, the jaws are short, thick and obtusely terminated ; and 

 the alveoli of the upper jaw reach as far back as the middle of the cavity which 

 intervenes between the nostril and the orbit, and which Goldfuss terms the " cavitas 

 ntiermedia." 



In the solid or imperforate part of the upper jaw anterior to the nostril the 

 Pterodacti/lus longirostris has twelve long subequal teeth, followed by a few of smaller 

 size : the same part of the jaw in the Fter. crassirostris has but six teeth, of which 

 the first four are close together at the end of the jaw, and the first three shorter than 

 the rest. The " cavitas intermedia" in P. longirosfris is much smaller than the nostril : 

 in the P. crassirostris it is larger than the nostril. Were these two species of 

 dentirostral Pterosauria to be taken, as by the modem Erpetologist they assuredly 

 would, to be types of two distinct genera, the name Pterodacti/lus should be retained 

 for the longirostral species, as including the first-discovered specimen and type of the 

 genus ; and the crassirostral species should be grouped together under some other 

 generic name. 



Pterodactylus CuviERi, Bowerhanh. 'Pterosauria,' Plate 3, figs. I — 7 ; Plate 4, 



figs. 1 — 3. 

 'Proceedings of the Zoological Society,' January 14th, 1851. 



The specimen of gigantic Pterodactyle, exhibited and so named by Mr. Bowerbank 

 at the meeting of the Zoological Society, January 14th, 1851, and which he has 

 confided to me for description in the present Monograph, consists of the solid anterior 

 end, i. e., of the impei'forate continuous bony walls, of a jaw, compressed, and 

 decreasing in depth, at first rapidly, then more gradually, to an obtusely pointed 

 extremity. As the symphysis of the lower jaw is long and the original joint oblite- 

 rated, and its depth somewhat rapidly increased by the development of its lower and 

 back part into a kind of ridge in some smaller Pterodactyles, the present specimen, 

 so far as these characters go, might be referred to the lower jaw, and its relatively 

 inferior depth to the upper jaw in the Pter. giganteus, would seem to lead to that 

 conclusion. But the present is plainly a species which has a relatively longer and 

 more slender snout, and the convex curve formed by the alveolar border, slight as it 

 is, decides it to be part of the upper jaw. The lower jaw, moreover, might be 

 expected by the analogy of the smaller Pterodactyles to be flatter or less acute 

 below the end of the symphysis. 



The specimen of Pferodactijlm Cuvieri consists of the anterior extremity of the 

 upper jaw of seven inches in extent, without any trace of the nasal or any other 



* Goldfuss, Beitrage zur Kenntniss Verschiedener Reptilien der Vorwelt, 4to, 1831, sec. i. Tabs, vii, 

 viii, ix. 



