332 KAMAKICHI KISHINOUVE: 



has the front margin nearly vertical. In the Katsuwonidae the lower anterior 

 corner of the lamellar portion is well produced, except in the genus Euthynnvs. 



The supraclavicle is a small elliptical bone, more or less pointed at the 

 anterior end, and thickened at the lower nuirgin. At the anterior pai't this 

 bone fits between the posterior process and the lamellar portion of the post- 

 temporal. The principal part of the supraclavicle rests on the dorsal extended 

 part of the clavicle. On the irmer side of the neck of the supraclavicle a 

 strong hgament, which I shall call the clavicular ligament, is inserted with a 

 broad attachment. The ligament connects the axial skeleton with the pectoral 

 girdle. In the Scombrida? the anterior neck and the exterior vascular gi-oove 

 are not conspicuous ; but the inner venti'al ridge is well developed. In the 

 CybiidfB the neck is not distinct, except in Sarda, neither is the inner venti'al 

 ridge «veil developed. The vascular groove is faint and foimd in the anterior 

 median part. In the Thunnidse the neck and the inner ventral ridge are very 

 conspicuous. The shallow, vascular gr.iove is found at the posterior lower 

 margin. In the Katsuwouidse the bone is nearly the same as in the preceding 

 family ; the vascular groove is deeji and conspicuous. In Eidliymnis and 

 Auxis, moreover, a lai'ge tendon is inserted just behind the attachment of the 

 clavicular hgament. The tendon is the terminus of a hypaxiixl siiuill cone of 

 some anterior myotomes, about five in number. Thus the supraclavicle 

 is connected to the axial skeleton with a strong sti-aight, ti-ansverse hgament, 

 and indirectly with a hyptxial, longitudinal tendon. 



The clavicle is a large curved bone, broad at the dorsal end, thin and 

 pointed at the ventral end. The main stem con-sists of two wings, the exterior and 

 interior, which meet at the anterior margin. At the dorsal anterior cxjmer there is 

 a pointed process. In the Scombridie the exterif)r wing is neaily vertical to the 

 interior wing at the anterior part, and the lower anterior extremity is turned more 

 or less externally. In the Cybiidae the exterior wing is wide, and is bent 

 backward with an acute angle, and the posterior margin of the exterior wing 

 is piU'allel to the interior wing. The anterior margin of the bone is mostly 

 rounded. In the Thunnidse the exterior and intoiior wings meet in an angle 

 approaching a right angle, and the exterior wing is not well developed at the 

 lower half. The exterior wing is pnxluced interiorly beyond the anterior 

 margin of the lx)ne, at the doi-Sid part, with the same inclination. In the 



