55 



the middle it is constricted and flattish as well as tlie ulna. The 

 latter however has a small convexity in the middle of its outer 

 margin under the semicircular olecranian process — ' 



Length of cubitiTS 



Width at base, inchuling olecranian apophj-se 



Width at neck .. 



Length of the radius 



Width at top 



Width in the middle , 



The carpal bones are in the Enpliysetes not so far separated 

 from each other by cartilage as in the Cafodon. They are seven 

 in number, viz. : two linear transverse bones and five of a flat, 

 round, irregular shape, a small hexagonal one of which is placed 

 between one of the transverse bones and the metacarpal bone 

 of the thumb. This transverse carpal bone is subtriangular, 

 and placed at the termination of the radius. The remaining 

 thin transverse bone is trapezoidal and situated between the 

 base of the ulna and the two outer carpal bones. The forefinger 

 has also two large flat carpal bones, placed between the corner of 

 the radius and the metacarpal bone of the forefinger. Of these 

 two carpal bones the one nearest the radius is pentagonal, and 

 the other hexagonal. Prom one side of the hexagonal bone 

 proceeds the metacarpal bone of the third finger. The largest 

 carpal bone, which is subpentagonal, lies between the trapezoidal 

 transverse carpal and the metacarj)al bone of the fourth finger, 

 while a small subquadrangular carpal bone joins the outer edge 

 of the linear trapezoidal carpal with the metacarpal bone of the 

 little finger. This position of the carpal bones among them- 

 selves, so widely different from the disposition of them in the 

 pectoral fin of the true sperm whale, is nevertheless certain ; 



