Geological Society. 317 



The skull is very similar to that of C. vetulus ; but the third 

 premolar is entirely in advance of the hind margin of the 

 foramen infraorbitale, whilst it is below it in the majority 

 of the other South-American dogs. 



in. lin. 



Length of skull 5 2 



Distance of orbit from incisors 2 2 



,, foramen infraorbitale from incisors . . 1 9 



„ fourth molar from incisors 1 9 



Length of nasal bone 1 9 



Least width of interorbital space 1 



Distance of incisors from hinder palatal margin . . 2 7 



„ between the fourth molars 10 



fifth , 8^ 



„ between the canine and fourth molar. . 11 



Length of three posterior molars 1 



Greatest width between zygomatic arches .... 2 10 



Number of caudal vertebra 23 ; length of the series of 

 caudal vertebras 13 inches. 



in. lin. 



Length of humerus 4 6 



,, idna 4 11 



„ radius 4 1 



„ fourth metacarpal 1 11 



„ femur 4 11 



„ tibia 5 



„ third metatarsal 2 3 



P.S. The Zoological Society has received, through G. H. 

 Hawtayne, Esq., C.M.Z.S., a second specimen from Deme- 

 rara, which seems to be perfectly identical with the one 

 described here. 



PROCEEDINGS OF LEARNED SOCIETIES. 



GEOLOGICAL SOCIETY. 



May 28, 1879.— Henry Clifton Sorby, Esq., F.R.S., 

 President, in the Chair. 



The following communications were read : — 



1. "On the Endothiodont Reptilia, with Evidence of the Species 

 Endothiodon uniseries, Owen." By Prof. R. Owen, C.B., F.R.S., 

 F.G.S., &c. 



The author referred to the characters assigned by him to his 

 Endothiodon bathystoma, which had the alveolar borders of both 

 jaws toothless, perhaps covered with horn during life, as in the 

 Chelonians ; whilst within this border there were three series of 



Ann. & Mag. N. Hist. Ser. 5. Vol. iv. 22 



