40 NEW YORK STATE MUSEUM 



alily apply in general to all of the Cathartidae, it having been noticed 

 l)y a niimiber of anatomical writers of authority, Owen among 

 others, who speaks of it in his Aiiotoniy of Vertebrates. Undoubt- 

 edly age has much to do with the condition, and I am quite sure it 

 has among- the Falconidae where the same condition exists. Mr 

 F. A. Lucas, who kindly examined the specimens of the Old World 

 vultures in the Natural Science Establishment at Rochester for me, 

 writes, " You will notice that the right sternal foramen of 

 Neophron is closed (referring to a specimen sent to the Army Medi- 

 cal Museum) ; this was also the case wnth a second specimen, while 

 a third, somewhat younger, had the foramen open, but much smaller 

 than the left. A specimen of Neophron from North India has both 

 foramina open, and there are a few trifling differences between its 

 skull and that of the Abyssinian specimens." 



The keel of the sternum in Gyparchus has the anteroposterior 

 curve along its lower margin, as we find it in Gymnogyps and 

 Sarcorhamphus ( S . g r y p h u s , G . c a li f o r n i a n u s) ; this 

 outline is faintly imitated by Catharista. but in this bird the border 

 is not nearly so thick in proportion. Cathartes has a convexity 

 peculiarly its own, as distinguishing it from others of the family. 

 The sternum is eminently falconine among the Old World vultures 

 in its general form and outline. 



Professor Owen, contrasting the relative lengths of the segments 

 of the pectoral limb as observed in the class, refers to it as found 

 in the " powerful raptorial flyers," as showing an intermediate and 

 more harmoniously balanced proportion of the several segments. 

 This is the case, in a marked degree, with our American vultures, 

 for here we find almost perfect examples of relative proportionment 

 among arm, forearm, and pinion, not only as regards lengths, but 

 the calibers of these long bones. We present a table of the lengths 

 of segments of the pectoral limb, given in centimeters and fractions 

 of the same, for the members of the family under consideration, 

 and add also measurements taken from Gypogeranus and Neo- 

 phron percnopterus for the sake of comparison. In all 

 of the long bones the straight line joining the points farthest apart 

 in distal and proximal extremities was taken as the line to measure 

 upon ; in the pinion, it was the straight line let fall from the highest 

 point in the metacarpus to the extreme tip of the distal phalanx, 

 the limb being closed. 



