the sides of the body made up of cobalt spots. Scales are more deciduous than in other species, 

 and where they come off the body is a brownish color. The snout tapers sharply, and the length 

 of the upper jaw is slightly more than twice that of the lower jaw. The lateral line is extraordi- 

 narily obscure, but when carefully examined it can be seen to be not simple but complexly 

 branched, a characteristic of this species. 



The color of the flesh is not greatly different from that of the striped marlin or the 

 white marlin, but this species generally contains more fat, and those taken in Formosa from 

 March to May are sometimes called "oily spearfish. " The flavor is considered inferior to that 

 of the striped marlin, but this depends upon the season jind the area, and those taken around 

 April and May make extremely delicious sashimi . 



These fish are particularly abundant in the open seas of wajrm latitudes, and they ap- 

 pear everywhere in the North Equatorial Current. In the coastal waters of the Ogasawara 

 Islands they appear aifter the striped marlin. They range farther to the north, but the northern 

 limit of their distribution is not known. In the southern portion of the Kuroshio, that is off 

 Fornnosa and the Philippines, they gradually increase in abundance beginning around March and 

 reach their peak around August and Septennber. This does not differ greatly fronn the situation 

 in the Ogasawara area. In August and September they are rather abundant in waters west of 

 Kyushu and the vicinity of Saishuto (Quelpart Island). They spawn east of Luzon from May to July. 



6, Broadbill swordfish, Xiphias gladius (Linnaeus) 



Swordfish (England-America). 



This fish belongs to a different family from the spearfishes listed above. It is also 

 called meka and tsun, the former name being used in the area around Tokyo and the latter being 

 employed in Kyushu. 



The upper jaw is very long, being more than 7/10 of the length of the body. In most 

 of the spearfishes, the upper jaw is slender and cylindrical, but in this species it has the form 

 of a two-edged sword. A remarkable characteristic of this fish is the complete absence of ven- 

 tral fins, of which there is not even a trace. It also differs notably in outer appearance from 

 the other spearfishes in that there are no scales, both jaws are without teeth, and the keels on 

 the caudal peduncles, of which there are two pairs in the istiophorids, are single in this species. 

 The back is bluish-black with a leaden cast, and the belly is white, but the fish appears to have 

 an all-over yellowish-brown cast. The flesh is nearly white, soft, very oily, and not particu- 

 larly prized as sashimi. It is however, palatable when cooked and seasoned and is greatly liked 

 by Anne r leans. 



This fish has a wide range of distribution and is known from warm seas throughout 

 the world. In Japanese waters, it is abundant off northeastern Japan and although a fish of tenn- 

 perate seas, it is numerous in rather high latitudes. It is taken by harpooning and by the long- 

 line fishery. 



In addition to these tunas and spearfishes, the tuna longline fishery takes cybitds, 

 dolphin, skipjack, nnoonfish, and sharks. Aside from the sharks, these other fishes can hardly 

 be said to be important in ternns of numbers. The sharks not only are taken in large numbers 

 and have an innportant significance as part of the catch, but they also demand attention as pests 

 which damage the fish caught on the longlines. Leaving aside this purely commercial signifi- 

 cance, they are worthy of considerable attention from the biological standpoint. 



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