3-2o Dorsal fin height only slightly greater than the body 

 depth, less than body depth in the central portion of 

 the fino Body rather stout c ^ ....... o Genus Kajikia 



Genus Tetrapturus Rafinesque, 1810 



The smallest in size among the fishes of this familyo The body 

 is long and slender and markedly compressed laterallyo The snout is 

 shorto The posterior rays of the dorsal fin are hi^ and the pectoral 

 fins are shorto Jordan and Evermann record six species in this genus, 

 of which five occur in the Indo -Pacific region. Among them are included 

 some which clearly belong to other genera. One species occurs in 

 Japanese waters, 



1 , Tetrapturus angustirostris Tanaka 



In Japanese fiTraikajikij , sammakajiki , or sugiyajnao 



Figure 18, —Short-nosed spearfish. 



The first dorsal fin has 49 to 53 rays, of which the first three 

 are spines. Eleven to 13 of the rays immediately following the first 

 three have branched tips, and the remaining 35 to 37 rays are spines. 

 The second dorsal has 6 soft rays, and the first anal has 2 spines and 

 12 soft rays. The second anal fin is composed of 7 to 12 rays. The 

 vertebral count is 12 / 12 s 24, 



Body length is about 7 times the greatest body depth, and about 

 8 times the depth of the body at the insertion of the first anal fin. 

 The body length is about 6o 3 times the length of the snout. The snout 

 length is 1,4 times the head length. The head length, excepting the 

 snout, is about 3,3 times the diameter of the eye. The greatest body 

 depth is 3,8 times the depth of the caudal peduncle. The ratio of 

 upper jaw to lower jaw length is 1,3 (This is a comparison of the dis- 

 tance from the posterior edge of the maxillary to the tips of both jaws. 



This species is the smallest of the spearfishes. The trunk is 

 conspicuously compressed laterally. The upper jaw is short. Toward 

 the caudal peduncle the body gradually becomes cylindrical in cross 

 section, and on each side of the caudal peduncle there are two keels. 

 The scales are bony and slender, and their posterior ends are sharply 

 pointed and buried in the skin. The lateral line, which is clearly 

 evident, follows a sonewhat wavy course above the pectoral fin. 

 Posterior to the tip of the pectoral fin it runs in a straight line 

 slightly above the median line of the side of the fish. 



56 



