AKT. 15 AIs^ATOMY OF THE EARED AND EARLESS SEALS HOWELL 25 



shape. This places the vertebral border almost parallel with the body 

 axis. In the Zalophus there is an epiphyseal cartilage all along the 

 vertebral border, in the skeleton under consideration ossified only at 

 the gleno-vertebral end. In the Phoca the only present indication 

 of cartilage is the extensive gleno-vertebral projection, becoming 

 more or less completely ossified with age. The degree to which this 



ET>\SUBSCAPj 



SUPRASTiN 



B1CE.PS 

 AiTL.&CAT.lNf 

 DELTOID 



RHOtAB. ANT. 



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Fig. 



-Latekal view of the left scapula of Zalophus {Z) and Phoca 

 hispida (p) with areas of muscle attachments 



condition obtains within the Phocidae is unknown at present because 

 cartilage often is damaged or disappears entirely during cleaning of 

 the skeletons. In the Zalophus the spine, placed not only relatively 

 but actually farther caudad, terminates in a short acromial process, 

 virtually absent in the Phoca, but it is difficult to give a myological 

 reason for this difference. There is considerable generic variation 



