THE OSTEOLOGY OF VULPES MACROTIS. 407 



All of this arrangement agrees with what Professor Flower found in a domesticated 

 dog, Canis familiaris. The sternal or costal ribs appear to have a feeble ossifica- 

 tion of a somewhat granular nature. 



Their are thirteen pairs of true vertebral ribs, the first pair being the shortest 

 and the ninth pair the longest. From the 8th to the 13th pair inclusive they are 

 very slender, but slightly .curved, and decidedly rod-like. The first pair of ribs are 

 short, rather stout, and subcylindrical in form. They are likewise curved. In the 

 first five pair, and especially in the first three pair, the sternal moities are dilated 

 and flattened from side to side. All the leading pairs of these ribs have their 

 vertebral ends completely developed, possessing all the characters known to be 

 present in the ribs of the ordinary mammalia. As we pass posteriorly the features 

 of the vertebral heads become gradually more rudimentary, especially in the matter 

 of the disappearance of the neck, the tubercle and the angle, the capitulum alone 

 remaining for articulation with the vertebra above. The last two or three pairs of 

 the costal ribs do not meet the sternum, but come in contact with the same struc- 

 tures in advance of them. Vulpes velox in all probability agrees with V. macrotis 

 in all this part of its skeleton ; that is, in its vertebral column, sternum and ribs. 



The Shoulder Girdle. 



Many anatomatists have touched upon this part of the skeleton of the Canidse 

 in osteological works. For example, Sir Richard Owen, in his second volume of the 

 Comparative Anatomy and Physiolgy of Vertebrates, on page 510, said in effect 

 that in the Canidse the scapulae, and especially the limb-bones, are longer and 

 more slender relatively than in the Viverridae, Mustelidae and in the plantigrade 

 carnivora. The clavicles are reduced to mere styles. Years afterward, Sir Wm. 

 Henry Flower, in his Osteology of the Mammalia, stated that in " the carnivora 

 the anterior and posterior fossae of the scapula are nearly equal in area. [Refers to 

 the scapula of the domestic dog as an example.] The spine and acromion are fairly 

 developed, the latter often with a broad metacromial process. The coracoid is 

 much reduced." According to Parker " a portion of the scapula, near the coracoid 

 border, ossifies from an independent centre. The clavicle is sometimes absent, and 

 when present varies much in its development, but is always rudimentary and sus- 

 pended in the muscles, never reaching either the acromion or sternum. In the 

 Felidae it is slender and curved, being longer than in any other members of the 

 order. In the Canidae it is very short, and rather broad and flat. In most of the 

 Ursidae it is absent." 



The clavicles in the skeleton of V. macrotis before me are missing, but there 

 is every reason to suppose that they agreed in their general characters with the 

 vulpine carnivora generally ; that is, in some respects they were rudimentary and 

 did not reach either the acromion or the sternum ; they have been lost in this par- 

 ticular specimen. 



The scapulcs, however, are thoroughly developed and strong, well-ossified bones. 



