300 KAM-iKICHI KI3HIN0ÜYE: 



bands, while the fish telonging to the genus Sarda have many longitudinal 

 bands on the back (fig. 33). In a small immature specimen of Sarda orientcdis, 

 (obtained on the east coast of Aomori-ken, I foimd 13 transverse bands, and in 

 these bands, five to seven, obhque longitudinal bands, were found, fishes 

 Iwlonging to the genus Gymnosarda have no markings at all (fig. 37). In 

 the Cybiidie dots and bands are generally few in number in immatvure forms, 

 and the markings increase in numter liy intercalation as the fish grows 

 larger. Cijhium niphoniiim imder 10 cm in length, and Cyhium liorcannm 

 under ca 20 cm lack mai-kings entirely. 



In adult tunnies we find no markings, except many silvery lines and dots 

 in the belly of certain species (fig. 45, 48). These silvery dote and lines are 

 not found in the other scombroid fishes. Adult bonitos have dark bands 

 generally ti'ansverse in the back ; but they are not conspicuous in the genu 

 Katsuwonus (fig. 53), as the bands are very broad and quite near each other. 

 Longitudinal bauds on the belly of Katsmoonus and dark spots in the thoracic 

 part of Eidhynmis (fig. 54) are characteristic to the respective genus. Generally 

 small immature forms of plecostean fishes are transversely banded and they 

 extend fi'om the doi-sal median line to the ventral median line. These bands are 

 broad an 1 they approach each other very closely, in the ThvmnidiB ; but in 

 the KatsuwonidfB they are rather nai-row, being more naiTow than the interval 

 l)etween them, and are short, not reaching the ventral meditui line. Small 

 immatui-e forms of TImnnus orientcdis (fig. 43) and Neothumus macrop'erm 

 have many dark tran-svei-se bands, which gi-adually disap\x^ar from the doi-sal 

 side, when the fish is about half a year old ; but the ventral part of these 

 bands remains all thi-ough hfe (fig. 45). As the fish grows larger, these 

 bands in the belly aa-e subdivided by a sei-ies of dots. Thesä boundary lines 

 and series of dots gradually inchne obliquely backwards, towards the veuti'iü 

 median line (fig. 45). In Parathwmus mehacJd of ca. 90 cui in length I found 

 veuti-al markings, but in lai'ger specimens they disappear entirely. In T/iunnus 

 rermo and Neothunnus rarus (fig. 48) hn-egular longitudinal bands of gi-ayish 

 colour are found in the belly, and they anastomose with each other, leaving 

 silvery meshes. In the former species the mm-king disappears in lai'ger 

 specimens, but in the ktter, it remains lifelong. Pigments and silvery 

 ingredients of bonitos m-e foimd at the surface of the skin. Therefore when 



