258 E S. Biggs — Skull of Amphictis. 



The first molar bears three small but well-marked tubercles. 

 Of these the inner one is the largest ; it is flanked by a promi- 

 nent internal cingulum which may be regarded as an incipient 

 fourth cusp. The outer tubercles are shifted mesially, leaving 

 a broad external surface which is elevated to form a marked 

 prominence at the acute antero-external angle. In outline the 

 anterior border is convex, the posterior concave. The second 

 molar has been lost from both sides of the specimen, but the 

 alveolas show that it was reduced to a single-rooted tooth. 



Base of the skull x 1. 



The characters of the base of the skull show affinities with 

 both the mustelines and the Viveridse. The alisphenoid canal 

 is present as in the viverines and the older fossil cats. The 

 otic bullae are well inflated and there is no inferior lip to the 

 auditory meatus, as is true of the viverines ; but the tympanic 

 walls are much thickened and inclose but a single cavity, into 

 which the meatus externus enters at the middle much as in 

 the mustelines. The paroccipital processes are free from the 

 bullge and are directed backward, downward and outward as in 

 the early Carnivora and Creodonts. The mastoid processes are 

 blunt and inconspicuous, but lie close to the meatus and form 

 part of its posterior wall as in certain mustelines. The pos- 

 terior nares open on a line with the last molars ; the pterygoids 

 are grooved infra-laterally. 



The posterior lacerate foramen opens at the posterior border 

 of the bulla near the stylo- mastoid as in Bassaris* and the 

 carotid foramen lies just in front of it as in that form. The 

 foramen ovale and the posterior opening of the alisphenoid 

 canal lead into a common fossa, as in the civets and the early 

 cats. The post-glenoid foramen opens at the extremity of the 

 anterior rim of the auditory meatus and is partially concealed 



* Flower, Proceedings of the Zoological Society of London, 1869, p. 10. 



