CREODONTA. 353 



and deep fossa. The patella is narrow, thick, and truncate at one end. 

 The proximal end of the tiUa exhibits a very prominent and well elevated 

 crest or spine, which bounds a deeply excavated fossa. The articular faces 

 are separated by a deep notch behind; the external is a little the larger and 

 is produced into a point outwards and backwards ; it lacks the notch of the 

 anteroexterior margin so distinct in Canis, but possesses an emargination 

 at the outer base of the crest, homologous with it. The general form is, 

 however, more like that of Canis than of Fells, and least like that of Ursiis. 

 The distal extremity of the tibia presents Carnivorous characters. The 

 two trochlear fosses are deeply impressed, the outer wall of the external one 

 being formed by the fibula only. The anterior marginal crest is more ele- 

 vated than the ijosterior, and presents an overlapping articular face between 

 the fossaj for a corresponding tuberosity of the neck of the astragalus. 

 The inner malleolus is entirely without the groove for the tendon of the 

 tihialis posUciis muscle, and therefore different from many of the digitigrade 

 Carnivora. It has an ovate truncate surface. On the anterior face opposite 

 the inner trochlear groove is a rather small but deep fossa. 



The astragalus has an elongate oblique neck and a navicular extremity 

 slightly expanded inwai-ds. The trochlear ridges are well elevated, and not 

 very oblique to the true vertical plane, being much as in the dog. The dis- 

 tal extremity is quite different from Felts, Hycena, Canis, and Ursus in having 

 a rather naiTow convex facet next the cuboid bone extending from front to 

 rear, and in having the navicular facet puUej-like or slightly concave in 

 transverse section, while it is strongly convex anteroposteriorly. This is 

 part of the peculiarity presented by the hind foot in this genus Behind 

 the navicular facet, on the superior face, is a tuberosity which stops the 

 flexure of the foot by contact with the tibia; a trace of it is seen in the dog. 

 The calcaneum has the compressed form of the digitigrades, but the broader 

 internal, and convex external astragaline facets resemble much more those 

 in the bears. The sustentacular facet looks as much forwards as upwards. 

 The cuboid facet is a frustum of a triangle with the apex directed inwards 

 and downwards. 



The metapodial bones are rather elongate, and flattened so as to be 



transverse in position. A second metatarsal is more flattened than corre- 

 23 c 



