76 
PACIFIC SCIENCE, Vol. VI, January, 1952 
No. 1 branch in the Hawaiian specimen, but 
inasmuch as the circulatory system was not 
injected, this blood vessel may have been 
overlooked. 
The coloration of the finlets in the Hawai- 
ian specimen differed from descriptions for 
this form given by other authors. Both the 
dorsal and anal finlets were bright yellow 
with broad black borders, similar to those of 
the big-eyed tuna, Parathunnus sibi. Kishi- 
nouye (1923: 439) notes that in T. orientalis 
the dorsal finlets are yellow, whereas the anal 
finlets are silvery; both are without a black 
margin. Godsil (1945: 187) states that in T. 
thynnus "... the finlets, though frequently 
yellow, are not edged with black.” Roedel 
TABLE 1 
Measurements* and Meristic Counts of a 
Specimen of Thunnus thynnus from Hawaiian 
WATERS 
Measurements 
Total length 1740 
Head length 497 
Snout to insertion first dorsal 531 
Snout to insertion second dorsal 950 
Snout to insertion anal 1069 
Snout to insertion ventral 540 
Insertion ventrals to anterior edge vent 560 
Greatest depth 450 
Spread caudal 561 
Length longest dorsal spine 189 
Length first dorsal spine 189 
Length second dorsal 268 
Length anal 251 
Length longest dorsal finlet 59 
Diameter iris 44 
Length maxillary 25 
Least depth caudal peduncle 47 
Greatest width caudal peduncle at keels 144 
Meristic Counts 
First dorsal spines 14 
Second dorsal rays 15 
Dorsal finlets 8 
Second dorsal plus dorsal finlets 23 
Anal rays 15 
Anal finlets 7 
Anal plus anal finlets 22 
Gill rakers (first gill arch) 12 + 24 
(1948: 60) similarly remarks that T. thynnus 
"lacks . . . the black edging of the finlets 
found on the yellowfin tuna when caught.” 
These discrepancies may be simply individ- 
ual color variations that exist within the 
species or real differences that show variation 
with geographical distribution. 
Until a more detailed comparison is made 
between T. thynnus from the eastern Pacific 
and T. orientalis from the western Pacific, the 
specific standing of these forms remains in 
doubt. 
REFERENCES 
Fowler, H. W. 1923. New or little-known 
Hawaiian fishes. Bernice P. Bishop Mus., 
Occas. Papers 8 (7): 3-20. 
1928. The fishes of Oceania, iii+540 pp. 
Bernice P. Bishop Mus., Mem. 10. 
Honolulu. 
Godsil, H. C. 1945. The Pacific tunas. Calif. 
Fish and Game 31 (4): 185-194. 
and E. K. Holmberg. 1950. A 
comparison of the bluefin tunas, genus 
Thunnus from New England, Australia and 
California. Calif. Div. Fish and Game, Fish 
Bui. 77: 5-55. 
Jordan, D. S., and B. W. Evermann. 1926. 
A checklist of the fishes of Hawaii. Pan- 
Pac. Res. Inst., Jour. 1 (1): 3-15. 
Kishinouye, K. 1923 . Contributions to the 
comparative study of the so-called scom- 
broid fishes. Tokyo Imp. Univ., Col. Agr. 
Jour. 8 (3): 293-475. 
Marr, J. C., and M. B. Schaefer. 1949. 
Definitions of body dimensions used in 
describing tunas. U. S. Fish and Wildlife 
Service, Fish Bui. 47 (51): 241-244. 
Roedel, P, M. 1948. Common marine fishes 
of California. Calif. Div. Fish and Game, 
Fish Bui. 68: 5-150. 
■* Measurements are in millimeters. 
