Temminck and Schlegel^ % Jordan and Snyder^ \ and Dr. Tanaka^ ^, 

 have reported on the species from Japanese waterSo The nresent writervl^j, 

 has reported two families^ four genera, and six species from Formosan 

 ■waters, and in recent years has classified the spearfishes of the western 

 Pacific in two subfamilies, five genera^ and six specieav^Sj^ The two 

 subfamilies^ 3 of the 5 generaj and 2 of the 6 species are new. 

 Accordingly, if the broadbill swordfish is added, the species occurring 

 in the western Pacific are seveno 



Such characteristics of the Istiophoridae as elongated bony scales, 

 the so-called reticulated gills, and the absence of gill-rakers are 

 shared with the Scombriformes, so it is thought that they are derived 

 from this latter groupo Furthermore, since in form they resemble the 

 juvenile stages of the broadbill swordfish, they are believed to be 

 probably an intermediate form between the Xiphiidae and the Scombridaeo 

 It is not, however, possible from a morphological comparison simply to 

 affirm this evolutionary relationshipo And viewed geologically the 

 fossils of the mackerels, spearfishes, and swordfishes appear parallel 

 to one another so that the above-mentioned relationship is not proved 

 from this angle eithero 



Key to the Families 



ao Elongated bony scales present,, Snout short, nearly round in 

 cross section,, Teeth present in both jaws™ Ventral fins 

 present! two pairs of keels on the caudal peduncleo Dorsal 

 fins close together . , . . o . • . . « o o o » » » o ,. Istiophoridae 



bo No scaleso Snout long, both upper and lower members gladiatOc 

 Teeth present in juveniles but absent in mature specimenso 

 No ventral fins; dorsal fins widely separatedo Single pair 

 of large keels on caudal peduncle o . o » . . . . . » . , o o o o Xiphiidae 



Family Istiophoridae 



Body long, trunk laterally compressed, caudal portion gradually 

 becoming cylindricalo Covered with elongated bony scales almost buried 

 in the skino Upper jaw projecting in the form of a spearj predentary 

 bone at tip of lower jawc Rasp=like teeth are present in both jawso 

 In mature fish the dorsal and anal fins are each divided into two 



'•'■•'•-' Temminck and Schlegelo 1850o Pisceso Siebold's Fauna Japonicao 



^^"^J Jordan, Do So and JoO, Snydero 1901o Jour« Collo Scio Imp, Univ<, 

 Tokyo", 15o 



(^3; Tanaka's Fishes of Japan, V"ol„ lo 2nd Ed. po 324o 

 (14} Nakamura, Hiroshio Taiwan Suishi Hokoku No, 10. 1938o 

 \i-o ) Nakamura, Hiroshio Studies of the Istiophoridae of Formosan 

 Iffaterso Scio Rpts„ Taihoku Impo Univo (unpublished)o 



54 



