WEALDEN CROCODILES. 633 



the tympanic pedicles are smootli, and terminate iu the usual transversely extended 

 concavo-convex articular surface. 



The tooth called "anterior canine" (ib., fig. 3, ?> c) is preserved, somewhat mutilated, 

 in each premaxillary. Sockets of smaller premaxillary teeth are faintly traceable. The 

 tooth termed "posterior canine'' (ib., >«, c) projects from the anterior part of the out- 

 swollen and convex border of the maxillary. From portions or traces of the other teeth 

 or sockets I estimate that there were from sixteen to eighteen teeth on each side of the 

 upper jaw. In the largest and least mutilated crowns of these teeeth the dental 

 characters of the genus Goniopholis are shown. 



In the ' Catalogue of the Osteological Series, Mus. Coll. Surgeons,' 4to, 1853, 

 p. 164, is described the specimen No. 75.:2, as "The skull of a Crocodile from Bengal 

 wanting the lower jaw, of a species {Crocodilus palustris ?) which is frequently found 

 inhabiting the larger ponds. It differs from the Cr. biporcatus of the Ganges in having 

 shorter maxillary and premaxillary bones in proportion to its length, and in having much 

 less developed prefrontal ridges ; the palatal suture between the maxillary and pre- 

 maxillary bones is transverse, not curved. The anterior extremities of the palatine bones 

 are narrower and more pointed. The number of alveoli is — premaxillary 5 — 5, maxillary 



J) 



14—14. 



The doubt indicated (?) arose from the inadequate characterisation by Lesson, of the 

 species described by him in the 'Zoologie' of the ' Voyage aux Indes Orientales de Belanger;' 

 but there is no reference of the specimen. No. 752, to the Crocodilns rhombifer, as is 

 affirmed by the author of the " Synopsis of the Species of Recent Crocodiles," ' Trans. 

 Zool. Soc.,' vol. vi, p. 140. I did not regard my doubt as justifying the sinking of Lesson's 

 " paliisiris " into a synonym, and of imposing a new specific, much less generic name. 

 But the osteological character of the palatal region of the skull, pointed out in my 

 ' Catalogue,' appears to be the chief of those relied upon by the author of that * Synopsis ' 

 for his genus Bomhifrons, of which the first character is : — " The premaxillary suture 

 straight, or rather convex forwards" (loc. cit., p. 139). The other characters are not of 

 specific value. 



The sutures of the premaxillary bones, I may remark, are of three kinds; one is 

 medial and unites the pair ; it is the " interpremaxillary suture :" the second is lateral, 

 uniting the outer or dental plate of the premaxillary with that of the maxillary ; it is the 

 " premaxillo-maxillary suture :" the third is transverse, more or less, and unites the 

 palatal plate of the premaxillary with that of the maxillary ; it is the " premaxillo- 

 maxillary palatal suture." Its modifications, added to other ditferences, when determined 

 to be constant, may aid in differentiating the species of Crocodilus proper, of Alligator, 

 and of Guvialis} 



^ Prof. Marsh, in his 'Introduction and Succession of Vertebrate Life in America,' 8vo, 1877, 

 writes (p. 21) : 



"The beds of the Rocky-Mountain Wealden have just furnished us with a genuine "missing link," a 



