244 PALEONTOLOGY 



Chelonia and birds which before were unknown ; the vertebrae 

 likewise exhibit very interesting deviations from the lacertian 

 type. The entire reconstruction of the skeleton of the Rliynclw- 

 sawrus may be ultimately accomplished, if due interest be 

 taken in the collection and preservation of the fossils of the 

 Grinsill quarries. 



The cranium of a Bhynchosaurian reptile with small palatal 

 teeth and obscure maxillary dentations, has been discovered 

 in the problematical sandstones, containing the LejJ^leuron, 

 near Elgin ; and adds to the probability (if their triassic age. 



Order VI. — Pterosauria. 



Char. — Pectoral members, by the elongation of the anti- 

 brachium and fifth digit, adapted for flight. VertebrsB 

 proccelian ; those of the neck very large, not exceeding 

 eight in number; those of the pelvis few and small. 

 Most of the bones pneumatic Head large ; jaws long, 

 and armed with teeth. 



The species of this order of reptiles are extinct, and peculiar 

 to the mezozoic period. Although some members of the pre- 

 ceding order resembled birds in the shape or the edentulous 

 state of the mouth, those of the present order make a closer 

 approach to the feathered class in the texture and pneumatic 

 character of most of the bones, and in the development of the 

 pectoral limbs into organs of flight (fig. 74). This is due to 

 an elongation of the antebrachial bones, and more especially 

 to the still greater length of the metacarpal and phalangial 

 bones of the fifth or outermost digit (fig. 74, 5), the hist 

 phalanx of which terminates in a point. The other fingers 

 were of more ordinary length and size, and terminated by 

 claws. The number of phalanges is progressive from the first 

 (fig. 74, 1) to the fourth (4), which is a reptilian character. 

 The whole osseous system is modified in accordance with the 



