144 U.S. NATIONAL MUSEUM BULLETIN 2 02 Vol. 2 



This genus may be recognized by the following characters: Branched 

 caudal fin rays 6 + 6, the outer branched ray weakly divided, and in 

 very small specimens sometimes unbranched; gill rakers on first gill 

 arch about 5 to 8 + 1 + 10 to 13; dorsal rays IX, 12 to 14, the first 

 two spines flexible, sometimes elongate, bannerlike, connected by 

 membrane with third dorsal spine; anal 111,12 or 13; pectoral rays 

 ii,10 or 11; a row of scales under eye and usually 2 scales on upper 

 part of opercle ; body compressed ; lower lip with a broad fold of tissue 

 on the side; dorsal profile of head steep, convex; interorbital space 

 strongly convex; nostrils small, anterior one a minute tube; jaws 

 equal; a pair of enlarged canines at front of each jaw, the pair in 

 lower jaw curved dorsally and fitting between the pair in upper jaw 

 when mouth is closed; canines of upper jaw curving downward; an 

 outer row of enlarged conical teeth at side of each jaw and a narrow 

 inner band of smaller ones; no posterior canine at corner of mouth; 

 gill membranes free from isthmus, with a broad free fold across isth- 

 mus; posterior edge of propercle free posteriorly as much as ventrally; 

 bases of fins except caudal, naked. 



The two species referable to this genus in the central and western 

 tropical Indo-Pacific may be distinguished by the following key : 



la. Dorsal rays IX, 13 occasionally IX,14; anal 111,13; pectoral rays ii,10; first 

 two dorsal spines of normal length; background coloration pale, with 

 brownish blotches or spots along midlengthwise axis of side, whitish and 

 brown bands extend behind eye, and one forward from eye to snout; 

 pelvics pale; plate 94, D X. macrolepidotus (Bloch) 



16. Dorsal rays IX, 12; anal 111,12; pectoral ii,ll, rarely ii,10; first two dorsal 

 spines flexible, elongate and bannerlike in young, becoming of normal 

 length in adult; color of young whitish with irregular dark brown lines, 

 and 8 or 9 brown lines radiating from eye, these reduced to 4 from 

 posterior side of ej'e of adult; head whitish; adults with broad white 

 bar at base of caudal fin, distal half dark; each scale with whitish center, 

 otherwise dark; pelvics dark brown; dorsal and anal fins barred; some- 

 times a blackish bar in axil of pectoral fin. X. taeniourus (Lacepfede) 



XYKICHTHYS TAENIOURUS (Lacepede) 



Plate 94,A,B,C 



Labrus taeniourus Lacepeide, Histoire naturelle des poissons, vol. 3, pp. 448, 518, 



pi. 29, fig. 1, 1802 (type locality, "Great Equatorial Ocean"). 

 Labrus hemisphaerhim Lacepede, Histoire naturelle des poissons, vol. 4, pp. 53, 



160, 1802 (type locality, "Great Equatorial Ocean"), 

 Julis vanikolensis QuoY and Gaimard, in Voyage de . . . VAstrolobe . . ., 



Zoologie, vol. 3, p. 704, pi. 20, fig. 1, 1834 (type locality, Vanikoro). 

 Novacula hoedti Bleeker, Act. Soc. Sci. Indo-Neerl., vol. 1, p. 59, 1856 (type 



locality, Amboina; ref copied). 



