24 PROCEEDINGS OF THE NATIONAL. MUSEUM vol. 6G 



trochlea and extend obliquely upward to a point about 10 mm. below 

 the center of the lower margin of the greater tuberosity. These de- 

 pressions may mark the position of the M. teres major and the MM. 

 pectoralis and latissimiis dorsi. The posterior surface (pi. 12, fig. 5) 

 is marked by a deep pit near the center of the shaft and below the 

 head. In this pit the short head of the M. triceps probably had its 

 origin. The inner trochlea is continued upward on the internal face 

 of the shaft to correspond with the shape of the greater sigmoid 

 cavity of the ulna. From an inferior view the capitulum or articular 

 facet for the radius is seen to be parabolic in outline and to follow 

 closely the contour of the lower end of the shaft. There is a distinct 

 crest or ridge between the capitulum and the inner trochlea. Both 

 of these articular facets are characterized by a transverse depression 

 formed by a series of small foramina. 



Measurements of left humerus 



mm. 



Greatest length (greater tuberosity to lower margiu) 104 



Exteroiuternal diameter of shaft near middle 47 



Anteroposterior diameter of shaft near middle 29. 5 



Exterointernal diameter of distal extremity of shaft 49. 5 



Anteroposterior diameter of proximal face of greater tuberosity 28 



Dorsoventral diameter of head of humerus 49. 5 



Exterointernal diameter of head of humerus 41 



Anteroposterior diameter of humerus through head 58 



CERVICAL VERTEBRA 



Only one of the cervical vertebrae was found and it (pi. G, fig. 3) 

 lacks the distal extremities of the lower transverse processes. For 

 this reason it is difficult to determine which one of the posterior 

 cervicals it actually represents. On making comparisons with the 

 cervical series of other living and fossil porpoises there appears to 

 be some grounds for believing that this vertebra is the fifth. The 

 centrum is broadly oval in outline and relatively thin. The anterior 

 epiphysis is complete, but a portion of the posterior one (pi. 6, fig. (V) 

 is missing. The articular facets on the prezygapophyses are elon- 

 gate, flattened, and slope obliquely inward. The neural arch is 

 slender and bears a short spine. Only a rudiment of the upper 

 transverse process persist-s, but the lower process is developed to an 

 extraordinary degree. The lower transverse process is thin, broadly 

 expanded, and imless it differed radically from other laiown por- 

 poises was rather long. This process is directed obliquely back- 

 ward and is perforated at the base by a large arterial canal. The 

 postzygapophysial articular facets are obliquely situated on the 

 lateral faces of backwardly projecting portions of the neural arch. 



