320 REPORT OF NATIONAL MUSEUM, 1884. 



guished from those of D. delphis. The inferior transverse process of 

 the sixth cervical is large and hamular.* 



The neural spines of the dorsal vertebrae are somewhat broader than 

 in D. delphis, but otherwise the vertebrae resemble those of that species 

 very closely. The first five pairs of ribs possess heads, which touch the 

 centra of the vertebras. Anterior zygapophyses become obsolete at the 

 thirtieth vertebra (counting from the atlas). They begin again at the 

 fortieth vertebra. There are nineteen chevrons, the first of which is 

 attached to the fortieth vertebra. 



The sternum consisted originally of three pieces, but the first two 

 are anchylosed together. The scapula is very similar to that of P. mar- 

 ginatus as figured by Messrs. Yan Beneden and Gervais (Osteog. des 

 Cetac£s, pi. XL, fig. 23), except that the acromion is considerably more 

 expanded. 



The formula for the phalanges is as follows : I, 2 ; II, 9 ; III, 7 ; IY, 

 3 $ Y, 1. The position of the metacarpal of the pollex is somewhat pe- 

 culiar. It does not form a part of the radial margin of the hand, but its 

 outer border is in a line with the median axis of the first phalanx. On 

 the outer surface of the carpus a small bone is visible, situated between 

 the metacarpals of the first and second fingers and the bones reckoned 

 as scaphoid and trapezoid by Professor Flower. This should be a ru- 

 dimentary trapezium if the system of Professor Flower be adopted. 



The pelvic bones are about 8 centimeters in length and are sigmoid in 



outline. 



Measurements of the skeleton. 



Centimeters. 



Greatest breadth of atlas 13. 2 



Greatest height of atlas 9. 8 



Greatest breadth of first dorsal 9. 2 



Greatest height of first dorsal 8. 4 



Greatest breadth of first lumbar 19.5 



Greatest height of first lumbar 14. 1 



Greatest length of scapula 19. 7 



Greatest height of scapula 14. 1 



Greatest length of pectoral fin 34. 8 



Greatest length of longest rib in straight line 30. 6 



Greatest length of sternum 17. 5 



Greatest breadth of sternum 10. 4 



# I find that the possession of a large inferior transverse process is not a safe guide 

 to the position of the vertebra in the cervical series. In a large collection, of cervical 

 vertebrae of T. tursio, in some cases the inferior transverse process of the fifth vertebra 

 is greatly expanded and in other cases that of the sixth vertebra. 



