G. 1. Adams — Extinct Felidce of North America. 425 



distinct third trochanter which is connected above by a ridge 

 with the great trochanter and is continuous below with the 

 linea aspera externa. The shaft is more rugose than in the 

 lynx and is not quite as straight. The patellar surface is broad 

 and shallow and the condyles large. 



The tibia is absolutely and relatively shorter than in the 

 lynx, being not quite four-fifths as long as the femur, while in 

 the lynx they are of the same length. In the lion the tibia 

 is five-sixths the length of the femur. The condylar surfaces 

 are large and are separated only by a low spine. The shaft of 

 the tibia is compressed laterally and the cnemial crest is high. 

 The anterior tuberosity is rather far from the condyles. The 

 distal portion is quite different from that of the lynx or lion, 

 inasmuch as the articular surface is very oblique and the astra- 

 galar groove only slightly indicated. The malleolus is heavy 

 and straight. A distinct ridge rises on its anterior surface and 

 extends a short distance up the shaft. 



The fibula needs no special description. It is quite stout 

 and has sharp lines for muscular attachment and is free the 

 whole length of the shaft. Its distal end presents a large 

 articular surface for the calcaneum. 



The pes. — The calcaneum is slightly shorter than that of the 

 lynx owing to its tubercle being not quite so long. The sus- 

 tentacular portion is situated rather farther distally and the 

 facet is presented more nearly upward. There is no facet to 

 support the head of the astragalus as in the lynx. This last 

 mentioned bone extends much farther distally than in the 

 lynx although the neck is not proportionately longer. The 

 astragalus of Hoplojphoneus is larger, particularly the body por- 

 tion. Its trochlear surface is only slightly grooved and its 

 outer border very oblique. It is in these two respects very 

 primitive. The cuboid is somewhat larger than that of the 

 lynx, while the navicular is considerably wider and the tubercle 

 not so much reflected upon the head of the astragalus. Its 

 distal surface presents three distinct facets for the cuneiforms. 

 In these bones the relationship as regards the articulation with 

 the metatarsals is similar to that of the trapezoid and magnum 

 in the manus, the second metatarsal being nearly excluded 

 from any lateral articulation with the ectocuneiform. In the 

 modern cats this wedging in of the second metatarsal is a very 

 great element of strength. The ento-cuneiform is not so 

 much reduced as in the lynx since the first metatarsal is not so 

 rudimental. The length of the metatarsals is proportionately 

 even shorter than the metacarpals, being only four-sevenths as 

 long as those of the lynx. The first digit is not much reduced 

 and carries an ungual. 



