1867.] DR. J. E. GRAY ON THE SKULLS OF THE FICLID.E. 259 



nally, and has only a very slightly raised scarcely visible keeled ridge 

 on that part. This process is represented as rather more prominent 

 in M. de Blainville's figure of the sknll (Osteographie, Felis, t. {)) 

 than it is in the specimens in the British Museum. 



The peculiarity in the formation of the skull, which separates the 

 Lynxes from the Cats, is not very striking ; but as it is common 

 to the skulls of all the species of Lynxes, both from the eastern and 

 western hemispheres, it shows how important it is to observe even 

 slight differences. 



In the Felidce generally the upper processes of the intermaxillse 

 and the front edge of the frontal bone on each side are provided with 

 a more or less elongated conical process, which separates a part of 

 the nasal from the maxilla ; and in the Lynxes these processes are 

 very slender and so much elongated that those of the intermaxilla 

 and the frontals nearly or quite unite, and entirely separate the nasals 

 from the upper front edge of the maxillae. This is not altogether 

 peculiar to the Lynxes, the same structure being found in a Cat 

 which has been called F. marmorata ; and the processes of the inter- 

 maxillary, often very long, reach up one-third the length of the side 

 margin of the nasal in some, of the larger Leopards. But the lateral 

 processes of the frontal not being so long as in the Lynxes and F, 

 marmorata, the two processes do not unite and separate the nasal 

 bones from the maxillae as is found in all the species of the genus 

 Lyncus. 



The skulls of the species of true Cats are so similar and uniform 

 in their structure that they present very few tangible characters 

 for the separation of the species into groups. In looking at a small 

 series of skulls it is easy to perceive that some are remarkable for 

 having a broad rather lengthened nose and moderate-sized orbits, 

 and others a narrow, short nose, pinched up behind, and above with 

 a more or less distinct concavity on the sides in front of the orbits, 

 and the orbits generally large. The former structure is confined 

 to the skulls of the larger species, as the Lion, Tiger, Leopard, 

 Ounce ; and the second is more marked in the small kinds. If 

 a larger series of skulls is examined, the two forms gradually pass 

 into each other, and it is found that the intermediate gradation of 

 form occurs in the skulls of some of the species that are intermediate 

 in size between the two extremes ; while some of the skulls of the 

 middle-sized species retain the characters of the larger broad-nosed 

 species. 



In some species, while the skulls of the adult animals are similar 

 to those of the larger broad nosed group, the skulls of the younger 

 or half-grown specimens have the sides of the nose more or less con- 

 cave and narrower behind, like those of the second group. 



The skull of a Chinese Leopard, presented by Dr. Lockhart, from 

 Pekin, presents one of those anomalies in dentition which now and 

 then occur in most families of Mammalia. It has a small subcylin- 

 drical short tubercular grinder behind the flesh-tooth on one side 

 of the lower jaw, and none on the other, thus having on one side 

 the formula of dentition that is peculiar to the genus Canis. But 



