84 MEMOIRS OP THE CARNEGIE MUSEUM 



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tending throughout about one third the total length of the shaft. Superiorly this 

 ridge shows a much greater development than in either the modern felidse or 

 canidse. The articular surface of the radial condyle is more distinctly keeled than 

 in the felidse and in this respect is more canine in character. A very sharp ridge 

 continues upward from this keel along the posterior side of the bone and along the 

 external margin of the anconeal fossa. The ulnar condyle is somewhat interme- 

 diate between that which obtains in the modern canidse and felidse. Proximally 

 the deltoid ridge is only moderately developed. The bicipital groove is deep as in 

 the dogs, the head is subelliptical in outline with the greater tuberosity much ex- 

 ceeding the lesser in size. 



The Radius and Ulna. — PL XIX., Figs. 9-12. Both radii are present and in 

 good condition. The most remarkable feature of the bones of the forearm is their 

 diminutive length as compared not only with the humerus, but with the same bones 

 in modern canidse and felidse, more especially the former. While the lengths of the 

 humerus and radius in the present skeleton are respectively 185 mm. and 135 mm., 

 the latter being therefore a little more than one fourth shorter than the former I 

 note that the relative lengths of these bones in Felis tigris and the retriever dog are 

 respectively 270 mm. and 240 mm. and 183 mm. and 205 mm. Thus we see that 

 in the tiger the radius is only one ninth shorter than the humerus, while in the dog 

 it is nearly one eighth longer than the humerus. In Canis latrans the lengths of 

 these bones are 157 mm. for the humerus and 163 mm. for the radius, the radius be- 

 ing still somewhat longer than the humerus. These bones are not only proportion- 

 ately shorter than in the canidse, but they are stouter and more completely crossed 

 than in the dogs. In both these characters they resemble more closely those condi- 

 tions as found in the cats than in the dogs. The articular surface of the head of the 

 radius for the humerus is regularly concave and rather deeper than in the dogs and 

 suboval in outline. The inner margin of the head is much expanded and over- 

 hangs the shaft of the bone as in the cats. Anteriorly there is a small median 

 prominence. The surface for articulation with the lesser sigmoid cavity of the ulna 

 is carried far around on the internal side of the head of the radius by reason of the 

 enlarged coronoid process of the ulna which is feline rather than canine in char- 

 acter. The tubercle of the radius is rather prominent and there is a noticeable con- 

 striction between it and the head. On the postero-external side, and in about the 

 middle of the shaft of the radius there is an elongated rugosity which opposes a 

 similar one on the antero-external surface of the ulna. These rugosities served for 

 the muscular attachment of these bones. The distal end of the radius is consider- 

 ably expanded both antero-posteriorly and transversely and supports a triangular, 



