COMPARATIVE STUDY OF SCOMBROID FISHES. 
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venules forming a dark red rod of plexus with similar arterioles from the 
dorsal aorta. It is remarkable that tliis rod of vascular plexus is found in the 
tunnies which want the conical vascular plexus on the inner side of the liver” 
Kidneys are much elongated posteriorly, reaching to the segment of 
about the fifteenth vertebra. Ureters are united forming an acute angle 
under the thirteenth vertebra, and the common ureter is found behind the 
vertebra. Thus the ureters are shaped like the letter Y. 
Vertebral column rather slender, and the second vertebra is nearly as 
high as broad. The posterior caudal vertebrae are remarkably elongated. 
Parapophyses long and flattenei. They become more or less vertical in the 
eighth vertebra, turned .downwards in the ninth vertebra, and an arc] 1 from the 
eleventh vertebra. Haemal canal wide, especially in the precaudal region, 
where the breadth of the cavity is nearly equal to that of the middle part 
of the respective vertebra. In one specimen I found the dorsal and ventral 
spines of the 36th vertebra short and nearly horizontal, instead of long and 
covering those of the next vertebra. 
The colour is nearly black at the back, sides greyish with oblique 
transverse lines and series of dots of silvery white in alternation. Iris greenish 
yellow ; first dorsal greyish tinged with yellow ; tips of the second dorsal and 
dorsal finlets bright yellow ; pectorals black on the inner side, greyish or some¬ 
times yellowing on the outerside ; ventrals greyish, tinged with yellow ; anal 
and anal finlets bright yellow. 
Distribution very wide, found in the Indo-Pacific region. Prefers warm 
water, 15-25° C mostly in the water of ca. 20° C. Northern limit of the 
distribution is ca. 35° N, but, sometimes found beyond 40° N. Occasionally 
found in the Japan Sea, and is caught in Hokkaido, near Otaru, late in 
summer. Found in the Hawaiian waters and south Californian coast. 
Large specimens measure more than 7 m in length, and ca 2Q0 kg in 
weight, next in size to our common tunny. 
They swim near the surface of the sea, especially in summer, and 
closely approach the land ; but small immature fishes ca. 2 kg in w r eight are 
always in the off-shore grounds, accompanying a school of the striped bonitos. 
Larger ones are caught by troll-lines, long lines, drift-nets, circle nets, pound- 
nets, set nets, etc. Smaller ones are caught with rods and lines, circle nets, 
