NOTES ON THE CANID.E OF THE WHITE RIVER OLIGOCENE. 381 



process is unusually large, forming an incurved hook, which, however, does not appear 

 prominently when the scapula is viewed from the external side ; in the recent Canidce the 

 coracoid is reduced to much smaller proportions. A resemblance to the shoulder-blade 

 of Canis is to be found in the broad neck of the scapula and in the absence of any well- 

 defined coraco-scapular notch. The coracoid border is slightly concave at the neck, but 

 then curves forward and upward, giving great width to the prescapular fossa ; the gle- 

 noid border is, as usual, straight and is steeply inclined, so that the postscapular fossa, 

 which is very narrow distally, becomes very broad proximally. The spine is high and 

 ends in a very long and prominent acromion, which descends below the level of the gle- 

 noid cavity, which suggests that in this genus the clavicles were much better developed 

 than in the existing dogs. A very large metacromial process is also present. The meta- 

 cromion may be observed in most of the existing families of Carnivora, but it is seldom 

 so large and so prominent as in Oynodictis ; perhaps, the nearest approach to it among 

 modern genera is in Arctictis. 



The humerus is much more suggestive of viverrine than of canine affinities. As 

 compared with the bones of the forearm, or even with the femur, the humerus is elon- 

 gate, but it is short in proportion to the length of the back or loins. The head is 

 strongly convex and projects farther behind the plane of the shaft than in the modern 

 dogs ; the external tuberosity is a heavy, but Ioav ridge, which barely conceals the head 

 when the bone is viewed from the front ; a large, irregularly circular area near the 

 hinder end of this ridge plainly indicates the insertion of the infraspinatus muscle. 

 The external tuberosity is both lower and shorter than in the modern clogs, but the inter- 

 nal one is rather more prominent, and the bicipital groove is more widely open, more 

 internal in position and more of it is visible from the anterior side. The shaft is rather 

 long, and, when seen from the side, exhibits a sigmoid curvature, which is somewhat 

 better marked than in Canis. For most of its length, the shaft is laterally compressed 

 and has but a very short cylindrical portion before expanding laterally at the distal end. 

 Most of the ridges and prominences for muscular attachment are well developed, more 

 so than would be expected in so small an animal. The deltoid ridge is much more 

 prominent than in the recent dogs, and is more like that of the cats and viverrmes ; the 

 supinator ridge is likewise very much more prominent than in Canis, in correlation - 

 with the power of rotation of the radius, which Cynodictis appears to have retained in 

 almost undiminished degree. On the other hand, the rough ridge, which runs down 

 from the head upon the outer side of the shaft (spina humeri) and serves for the attach- 

 ment of the teres minor, anconeus externus and brachialis iiiternus muscles, is much 

 fainter than in Canis and the linea tuberculi minoris is very feebly marked. The supra- 

 trochlear fossa is very shallow and the anconeal fossa is much smaller and shallower 

 than in the modern representatives of the family, there being no perforation of the shaft 



