CENTRACION ZEBRA. 181 



Base of anal about one and one fourth times its length from that of the caudal 

 origin of first dorsal above the end of the pectoral base, hind margin concave 

 (convex in second dorsal) 



bands transverse, broad japonicus (page 184) 



Base of anal about two thirds of its length distant from the caudal 



origin of first dorsal above the hind portion of the pectoral base, hind margin 

 concave 

 bands transverse and broad to absent . . galeatus (page 185) 

 Base of anal nearly one length distant from the caudal 



origin of first dorsal above the forward part of pectoral base, hind margin 

 concave 

 spots black, small, scattered .... francisci (page 186) 

 Base of anal two thirds of its length distant from the caudal 



origin of first dorsal behind the end of the pectoral base, hind margin convex 

 spots black, moderate, more or less grouped in twos and fours 



quoyi (page 187) 



Centracion zebra. 



Plate 47, fig. 4-6. 



Centracion zebra Gray, 1831, Zool. misc., 1, p. 5. 



Cestracion zebra Richardson, 1846, Rept. Brit, assoc. adv. sci. for 1845, p. 195. 



Heterodontus zebra Gray, 1851, Chondropterygii, p. 65; Bleeker, 1856, Act. Soc. sci. Ind. Neerl., 1, 



Amboina, p. 71; Maclay & Macleay, 1886, Proc. Linn. soc. N. S. W., 10, p. 673, pi. 45. 

 Cestracion philippi GtJNTH., 1870, Cat. fishes Brit, miis., 8, p. 415 (part). 



Cestracion amboinensis Regan, 1906, Ann. mag. nat. hist., ser. 7, 18, p. 436; 1908, ibid., ser. 8, 1, p. 497. 

 Cestracion zebra Regan, 1908, Ann. mag. nat. hist., ser. 8, 1, p. 496. 



Body and head more slender, head more pointed and fins longer than those 

 of other species of the genus. In a 19 inch female the body cavity is less than 

 half of the total length. Head one fifth of the total, orbital ridges strong, low; 

 snout blunt. Orbit elongate, half of interorbital space, more than one tliird of 

 snout. Spiracle small, below the hind edge of the orbit. Mouth narrow, with 

 labial folds on both jaws; lower folds as long as the space separating them; upper 

 very short, not reaching half way to the narial valves; with a short groove behind 

 the angles. Teeth in young quincuspid, becoming tricuspid with acquisition of 

 the molars; molars elongate with a longitudinal keel. This keel, in the specimen 

 described, Ues more to the outer side of the tooth than on such species as C. quoyi 

 and C. francisci; it is as if the tooth were turning outward to present more of its 

 inner side as a grinding surface. On older specimens the cusps and keels are 

 worn away, the molars are more swollen and the symphyses are proportionately 



