16 PEOCEEDINGS OF THE NATiONAL MUSEUM vol. 70 



process of the sternum, leaving a vacuity between. Most of the 

 sterna are relatively flat, but that of 240002 is much curved in a 

 sagittal direction, the convex aspect being directed ventrad. 

 The Cetacea have no clavicles. 



ANTERIOR LIMB 



The scapula is as shown in Figures 6 and 7, and described by 

 Allen. There is very little variation in the scapula proper, but a 

 great deal, constituting 100 per cent, in the width of the acromial 

 process. The coracoid process is fairly uniform save in 240002, in 

 which there is a well-marked accessory process extending ventrad. 

 This suggests some sort of muscle attachment, but in the two speci- 

 mens dissected there was no muscle connected with either of these 

 processes, and in comparison with most cetaceans their development 

 is very weak. 



From the prepared specimens it is impossible to secure the length of 

 the fore limb for the reason that some of the more distal elements, 

 including the cartilage, are missing. In the material available the 

 humerus may be practically as long as the radius but it is usually 

 somewhat less (from 86 to 99 per cent). Details of especial interest 

 are the large medial tuberosity, to which are attached the subscapu- 

 lars and mastohumeralis, showing considerable variation in its 

 precise configuration; and the infraspinous fossa, located toward the 

 cranial border of the lateral aspect. It should also be noted that the 

 distal extremity of the humerus is much flattened in a latero-medial 

 direction, and that the articulation at this point is immovable. 



As illustrated, the central portion of the radius is almost twice as 

 broad as of the ulna. The former bone has no prominent features, 

 and the latter, little of interest save the olecranol process, upon 

 which is inserted the very decadent triceps. It is very slightly 

 developed in comparison to that of most whales. 



The carpal elements are as figured by Allen (p. 253). There is 

 very little variation save in the degree of ossification, and hence 

 separation, of the different bones, this depending upon age. 



The second digit is evidently the longest, and in the only specimen 

 in which the distal end is not missing, it has eight bones, including 

 the metacarpal. It seems that the second phalanx of the pollex is 

 the one last to form, and hence, is entirely absent in the younger 

 individuals. 



PELVIC BONES 



In 240862 the pelvic bones measure 36 mm. in length and were 

 located barely caudad of vertical to the vulva, being 40 mm. from the 

 midventral line, to which they are approximately parallel, and there- 



