TUKSIO BOKEALIS. 81 



Ball's figure the central portion of tlie under side of the flukes is white. 

 It should be remembered that the individual which Peale sketched was 

 probably youiiy, being- only about 4 feet long. Mr. Ball's specimen was 

 a male 8 feet 1 inch long. 



Scammou also figures this species in his Marine Mammalia (PI. xix, 

 fig. 3). He gives the colors as in Mr. Ball's sketch, but makes the ft)rm 

 much more robust and the head high like that of a young Ilyperoodon. 

 We have no means of knowing whether this figure was made from ineui- 

 ory or from a captured specimen of the species. 



The general color of the specimens obtained by Br. Hilgendorf, in 

 Yeddo, Japan, was black. On the belly is a white area, which in the 

 young individual begins on a line with the eye, but in the adult extends 

 farther forward and ends on a bluish fork, which goes to the corner of 

 the mouth. The anterior third of the lower jaw is whitish violet, and 

 the margin of the lower lip is black. 



The following measurements were taken by Mr. Ball. A part of them, 

 reduced to centimeters, have already been given in comparison with 

 Lesson's measurements of L. peronii on page 80. 



Mcasuremcnis of Tursio horcalla {Peale), male, laken 200 miles off Cape Mendocino, Cali- 

 fornia, Ovtoher, 18G8. 



Incbes. 



Leugtli over all <^)7. o 



Extieiiiity of suout to angle of mouth tt. 75 



Extremity of suout to eye 13. 



Extrouiity of snout to blowhole 14. 



Extremity of suout to anterior edge of pector I lin 25. 



Extremity of suout to posterior edge of pectoral liu 28. 5 



Angle of mouth to eye 3. 75 



Height of eye above line of mouth 0. 75 



Length of anterior edge of pectoral fin 12. 



Length of posterior edge of pectoral lin, from base to angle 3.5 



Length of posterior edge of pectoral iin, from angle to tip 5.5 



Width of pectoral fin at base 4.0 



Width of pectoral fin from posterior angle to middle of anterior margin 3. 5 



Length of beak 2. 5 



Length of portion of lower jaw protruding beyond upper 0. 5 



Breadth across the finkes ](j. 



Autero-posterior length of either fluke (i. 



Distance from median notch to extremity of either fluke 10. 25 



Distance from median notch to the ending of the superior margin or keel of the 



tail 2.0 



Height of the caudal peduncle at insertion of flukes 3. 75 



Diameter (from side to side) at same point 1.5 



Distance from notch of flukes to anus 22. 5 



Length of anus 1.0 



Length of genital slit 6. 



Distance from notch of flukes to genital slit 27. 5 



Length of penis 15. 



Girth of head at eyes 2C). 5 



Distance around head from eye to eye below 12. 5 



Distance between pectoral fins 12. 



18378— Bull. 36 G 



