Jordan: Elephenor, A New Genus of F"ishes from Japan. 331 



Analysis of Genera Related to Pteraclis. 

 (Dorsal and anal fins composed exclusively of spines.) 

 .4. Dorsal and anal spines very slender, close set, most of them almost hair-like. 

 B. Pteraclid-^. Scales rather large, firm and hard, more or less lobate; 

 anal fin beginning far forward, before the pectorals, its base 

 almost as long as that of dorsal; dorsal fin very high, continuous, 

 its spines very slender and flexible, highest anteriorly, dorsal 

 spines about fifty-three, anal spines about forty-three; both 

 dorsal and anal depressible in a basal sheath of large scales; 

 ventral fins very small, weak, I, 5 (or perhaps sometimes I, 3) 

 jugular, inserted below (or before) the eye; form of body ovate- 

 elliptical, much compressed; nape not greatly elevated; forehead 

 rounded, not subvertical. 

 C. Dorsal and anal fins each with one of the anterior spines much 

 thickened; dorsal fin beginning on tip of snout, and beginning 

 just behind eye, the long rays of dorsal and anal nearly reaching 

 caudal. Dorsal with about eight graduated spines in front, the 

 eighth longest; ventrals very small, the rays I, 5; vent directly 



below ej^es Bentenia.'' 



CC. Dorsal fin beginning on the snout before the eye, with two to four 

 graduated spines, none of them notably thickened; anal fin 

 similar, both very high; longest dorsal spine when depressed 

 reaching past middle of fin; ventral rays I, 5 or I, 3.. Pteraclis. ' 

 CCC. Dorsal fin beginning behind the eye with nine to thirteen graduated 

 spines in front, none of them enlarged; ventral rays I, 5. 

 D. Anal fin high, its first ray reaching bej'ond middle of fin; gradu- 

 ated spines of dorsal 10 to 13 Centropholis.^ 



* CenlrophoUs Hilgendorf, Sitzungsbcrichte Naturforschende Freunde, Berl., 

 1878, p. i; type CenlrophoUs pelersi Hilgendorf; off Tokyo. 

 DD. Anal fin of moderate height, its first long ray reaching only to 

 middle of fin; dorsal beginning over preopercle, with nine 



graduated spines Pterycombus.^ 



BB. Elephenorid.«; Scales very small, thin, caducous; dorsal sheath probably 

 caducous;^ ventral fins large, i, 5, inserted just before pectorals. 



- Bentetiia Jordan & Snyder, Journ. College Sci. Imp. Univ. Tokyo, XV; 1901, 

 306; type Bentenia cesticola Jordan & Snyder from the Kuro Shiwo (Japan Current) 

 off Misaki, Japan (C/. Plate LVI of this Article.) 



3 Pteraclis Gronow; Zoophylaceum, 1763, p. 136 and also in Acta Helvetica, VH, 

 1772, p. 44. Type Coryphcena velifera Pallas; Indian Ocean. Pteridimn Scopoli 

 (1777) and Oligopodus Lacepede (1800) are based on the same species. (C/. PI. LV, 

 lower figure, of this articles.) 



'" Plerycombus Fries, Kongl. Vet. Akad. Handl. Stockholm, 1837, pp. 14, 22, 

 PL II; type Pierycombiis brama Fries; Arctic Coast of Norvvay. (C/. Plate LVII, 

 upper figure of this article.) ♦ 



^ Bellotti's figure shows plainly a dorsal and anal sheath of scales. There is no 

 trace of these in our specimen. 



