310 FOSSIL REPTILES. 



others on a longitudinal line. Many fishes have them also on 

 a longitudinal line ; and this, probably, helped to cause the 

 mistake of Camper about this fossil reptile ; but the compa- 

 rison of the bones which have these teeth, will prove that they 

 belong to reptilia, and not pisces. 



The pterygoid bone in the monitor and iguana is not united 

 to its consimilar as in the crocodile, nor widened into a large 

 triangular plate. It is a bone with four branches : one pro- 

 ceeds forward, and unites^ itself to the anterior palatine ; the 

 second goes sideways to join the transverse bone, which unites 

 itself to the upper maxillary ; the third rests by a facet pro- 

 vided with a cartilage, on an apophysis of the basis of the 

 cranium ; the fourth goes back, and gives an attachment to the 

 muscles, but is not articulated to any bone. On the edge of 

 the anterior branch is implanted the series of teeth which cha- 

 racterizes the iguanas. The anolis have this bone wider in all 

 its parts, and the lower branch shorter. The monitors, on the 

 contrary, have all parts of the bone more slender, and have 

 no teeth there. 



There is a great resemblance to the iguanas in the pterygoid 

 bones of the fossil. The posterior apophysis of the right ptery- 

 goid, though seen from a mutilated specimen, being broken at 

 the end, still appeared to be equally long in proportion as that 

 of the iguana. The four apophyses of the other were very dis- 

 tinct. The principal specific difference was, that the internal 

 one was longer in proportion than in the monitor and iguana. 

 But there did not appear the slightest relation of form with 

 the palatine bone of fishes, and still less with their pterygoidean 

 bone. 



This bone, in the fossil, appeared to have had eight teeth, 

 which grew, were fixed, and replaced like those of the jaws, 

 though considerably smaller. 



From a large fragment preserved at Haarlem, M. Cuvier ob- 

 serves that the upper jaw was elongated and not much raised, 

 and that its edges along the external aperture of the nostrils 



