SHUFELDT : OSTEOLOGY OF THE STEGANOPODES 1 79 



" The coracoid is of the same length as that of carbo, 10 mm. longer than in urile ; 

 but, while the proximal end is but little heavier than in carho, the shaft and espe- 

 cially the distal end are much more massive. 



"The epicoracoid is prolonged upward into a sharper hook than in any of the 

 other species at hand, but this process is subject to considerable'variation with age 

 or in various individuals. 



" One humerus is a little longer than that of carbo, the other is of exactly the same 

 length ; both are much stouter, especially in the proximate half 



"The humerus is practically non-pneumatic, the foramina being very minute, 

 while the pneumatic foramina of carbo, though not large, are readily seen. 



" The humerus of urile differs from that of dUophus precisely as that of per- 

 spicillatus from carbo. 



" The ulna is distinguishable from that of carbo only by its greater weight, and 

 the same may be said of the humerus of iirile as compared with that of dilophus. 



"The fused metacarpals are slightly shorter and slightly stouter than in carbo, 

 and here again the same differences are observable between the metacarpals of 'urile 

 and dilophus. 



"The 'sacrum,' as a whole, is as long as that of carbo, but its component parts 

 are more heavily built. 



" It comprises six pre-sacrals, two true sacrals, and nine post-sacrals, and the 

 three ' sacra ' of perspicillatus agree with one another in these particulars. 



" Phalacrocorax carbo has six pre-sacrals, two true sacrals, and nine or ten post- 

 sacrals. P. urile has six, two, eight, and dilophus six, two, nine. 



" The hypapophyses of the anterior three vertebrae have been broken off, but 

 although the compressed centra are larger than in carbo, the hypapophyses seem to 

 have been smaller. 



"The six pre-sacrals present few salient characters, but the diapophyses of the 

 fourth vertebra lie at right angles to the vertebral column, while in the three other 

 species the diapophyses of this vertebra are directed forward. 



"The sacral and immediate post-sacral vertebrae vary in the development of 

 their parapophyses in all four species under consideration. 



" In all three specimens of perspicillatus the two true sacrals bear no parapophyses, 

 while the two succeeding vertebrae have them extended to, and anchylosed with, 

 the ilium. 



"The diapophyses and parapophyses of these vertebrae are united by a thin 

 plate of bone, but that this is due to age is shown by the condition obtaining in the 

 other species. 



