TUKSIO BOKEALIS. 81 



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

 It should be remembered that the individual which Peale sketched was 

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

 a male 8 feet 1 inch long. 



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

 tig. 3). He gives the colors as in Mr. Ball's sketch, but makes the form 

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

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

 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 ou 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. 



Measurements of Tiirsio horcaUs {Feale), male, laken 200 miles off Cape Mendocino, Cali- 

 fornia, October, 18G8. 



IdcIios. 



Leugtli over all 97. 



Extremity of suout to augle of month 1). 75 



Extremity of suout to eye Ui. 



Extremity of snout to blowhole 14. 



Extremity of suout to anterior edge of pec tor ;I tin 25. 



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



Augle of mouth to eye 3. 75 



Height of eye above lire of uiouth 0. 75 



Length of anterior edge of pectoral tin 12. 



Length of posterior edge of pectoral fin, from liase to angle 3.5 



Length of posterior edge of pectoral liii, from augle to tip 5. 5 



Width of pectoral liu at base , 4.0 



Width of pectoral tin from posterior augle to middle of anterior nuirgin 3. 5 



Leugth of beak 2. 5 



Length of portiou of lower jaw protruding beyond u[>per 0.5 



Breadth across the 11 ukes IG. 



Autero-posterior length of either tluke 6. 



Distance from median notch to extremity of either tluke 10.25 



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



tail 2.0 



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



Diameter (from side to side) at same point 1.5 



Distance from notch of flukes to anus 22. 5 



Leugth of anus 1.0 



Length of genital slit 0. 



Distance from notch of flukes to gen ital slit 27. 5 



Length of penis 15. 



Girth of head at eyes 20. 5 



Distance around head from eye to eye below 12. 5 



Distance betweeu pectoral tins , , ,., 13,0 



18378— Bull. 36--— G 



