1908.] Allen, The North Atlantic Right Whale. 327 



mm. 



Extreme length (near the anterior border) 555 



Transverse diameter of proximal end 240 



Antero-posterior diameter of proximal end 155 



Transverse diameter of distal end 350 



Antero-posterior diameter of distal end . 165 



Least transverse diameter of shaft 185 



The ulna, like the radius, is fan-shaped in its distal two thirds, and greatly 

 thickened proximally. The length of the distal border is rather more than 

 one half of the total length of the bone. Its principal measurements are as 

 follows: 



mm. 



Kxtreme length 480 



Transverse diameter of distal end . 280 



Least transverse diameter 110 



Antero-posterior diameter of distal end 90 



The carpal bones are wholly concealed in the hardened cartilage. 



The digits, five in number, decrease in length in the following order: III, 

 II, IV, V, I. Digit III, has 6 phalanges; digit II, 5; digit IV, 4; digit V, 

 3; digit I, 2. 1 (Plate XXIV, Fig. B.) In respect to the relative length of the. 

 digits, the number of phalanges in each, and the relative length of digit III, in 

 comparison to the whole limb, the manus in the present species closely resem- 

 bles that of Balvsna mysticetus. The number of phalanges in the several 

 digits appears to be variable, as. is known to be the case in other cetaceans. 



Measurements of Bones of the Manus. 



Digits. 



I II III IV V 



mm. mm. mm. mm. mm. 



Length of 1st phalanx 120 170 160 160 150 



" 2d " ?90 155 160 140 130 



" " 3d " 125 160 108 95 



" 4th " 95 120 ?60 



" " 5th 55 85 



" 6th ?60 



Total length 2 ?255 730 ?910 ?520 430 



The total length of the pectoral limb, measured from the most proximal 

 point of the head of the humerus to the tip of the longest digit, falls, in the 



1 True (I.e., p. 261) has given a different formula for this specimen, but on what authority is 

 not stated. My examinati9n, however, was made when all the parts were in situ, and were thus 

 drawn (see Plate XXIV, Fig. B). Mr. True refers to the impracticability of attempting to give 

 reliable formulae from mounted specimens in American Museums, and it may be added in cor- 

 roboration of this statement that the mounted specimen in this Museum, of which the digital 

 formula is given by True, proves on examination to have nearly all of the metacarpals and 

 phalanges restored in. wood! 



2 Includes the dried cartilage between the nodes as well as that terminating the digit. 



