FAMILY, XV— ACANTHURID^E. 203 



7. Acanthurus mata. D. ^jy, A. 2-3V5-. Brown, with black fins. Red Sea, seas of India to the Malay 

 Archipelago. 



8. Acanthurus Celebicus. D. afCf-g-, A. -f^, L. 1. 80. Brown, fins dark. Madras, Malay Archipelago. 



9. Acanthurus melanurus. D. jjL A. -^. Scales rudimentary or absent. Black band over occiput, 

 another across free portion of the tail. Seas of India to the Malay Archipelago. 



B. Broad teeth fixed in the jaws : 8 or 9 dorsal spines : ventrals not fully developed. 



10. Acanthurus hepatus. D. t^yo- V. 1/2, A. -j%. Slatey gray, covered by a deep brown band in the 

 upper half of its back, leaving an oval blotch of ground colour above the pectoral fin. Fins gray, spines and 

 rays orange, caudal yellow. Seas of India to New Guinea. 



C. Setiforrn moveable teeth dilated at their extremities : 8 or 9 dorsal spines : 5 ventral rays. (Ctenodon.) 



11. Acanthiwus strigosus. D. -^to, -A- 2~6-2T- Teeth setiform with dilated extremities. Body brown 

 lineated with bluish lines, red spots on the head. Red Sea, East coast of Africa, seas of India to the Malay 

 Archipelago and beyond. 



D. Broad teeth fixed in the jaws : 1 to 4 dorsal spines : 5 ventral rays. (Harpurus.) 



12. Acanthurus xanthurus. D. 2-1-2^, A. j-q-tt- Scales rudimentary, rough. Blackish, caudal yellow. 

 Red Sea, Bast coast of Africa and Ceylon. 



13. Acanthurus velifer. D. 2~§" : f~9> A. ^jj. Scales rudimentary. Dorsal and anal fins much elevated. 

 Brown, banded with narrow blue lines. Red Sea, East coast of Africa to the Malay Archipelago and beyond. 



A. Broad teeth fixed in the jaws : 8 or 9 dorsal spines : 5 ventral rays. (Bhombotides.) 



1. Acanthurus lineatus. 



Chatodon lineatus, Linn. Nat. Hist, i, p. 1246. 



Acanthurus lineatus, Bl. Schn. p. 214, t. xlix ; Lacep. iv, pp. 547, 549 ; Cuv. and Val. x, p. 223 ; Bleeker, 

 Sumatra, ii, p. 263 ; Giinther, Catal. iii, p. 333 ; Kner, Novara Fische, p. 210. 

 Ctenodon lineatus, Swainson, Fishes, ii, p. 256. 

 Acanthurus vittatics, Benn. Fish. Ceylon, p. 2, pi. ii. 

 Bhombotides lineatus, Bleeker, Arou, 1873, p. 3. 



B. v, D. rffe P. 15, V. 1/5, A. fr, C. 17. 



Length of head 5| to 5|, of caudal 2/7, height of body 1/3 of the total length. Eyes — diameter 2/9 of 

 length of head, 3 to 3|- diameters from end of snout, and l-§ apart. Profile from dorsal fin to snout obtuse. 

 The maxilla reaches 1/3 of the distance to below the orbit. Teeth— six or seven lobate incisors on either side of 

 the upper jaw. Fins — dorsal spines rather weak and a little shorter than the rays, interspinous membrane 

 scarcely notched. Pectoral as long as or slightly longer than the head. Caudal lobed, the upper the longer. 

 Scales — about eight rows between the lateral-line and the base of the last dorsal spine. Lancet-shaped spine 

 with a posterior process. Least depth of the free portion of the tail equal to 1/2 the length of the head. 

 Colours — head and upper two-thirds of body canary yellow, traversed by nine or ten more or less oblique blue 

 bands going from the head to the back and caudal fin : lower third of body reddish-gray. Two or three blue 

 bands pass down the summit of the head and the anterior edge of the eye towards the snout, whilst about 

 seven more pass across the cheeks to the bands on the body. Other blue bands pass upwards and backwards 

 from the hind edge of the eye to the bands on the body. Dorsal and anal fins dark with a gray margin. 

 Pectoral having its upper ray blue, and just internal to it a white line ascending 1/2 way up the ray : an arched 

 white band on lower half of pectoral fin on its inferior side. Ventral with its outer ray blue, its inner ones red. 

 Caudal with a semilunar blue band in its centre and a blue posterior edge. Bennett observes of Ceylon examples 

 that amongst six or seven specimens no two were alike in the arrangement of the blue and yellow streaks near 

 the caudal fin. 



Habitat. — Seas of India to the Malay Archipelago : common at the Andamans in December and Januarv 

 up to 10 inches in length. Bennett says : " the Seweyah (Acanthurus lineatus) is an extremely scarce fish on 

 the southern coast of Ceylon : inhabits rocky situations, and is not in request but for the gratification of the 

 naturalist. It seldom exceeds 16 or 17 inches in length." (p. 2.) 



2. Acanthurus leucosternon. 



Benn. Proc. Zool. Soc. 1832, p. 183; Bleeker, Batoe, iii, p. 237; Ganther, Catal. iii, p." 340. 

 Acanthurus Delisianus, Cuv. and Val. x, p. 193 ; Guer. Icon. Poiss. pi. xxxv, fig. 2 ; Griffith, in Cuv. 

 Anim. Kingdom, Fishes, pi. xxxiii, fig. 2. 



B. v, D. ^^ P. 16, V. 1/5, A. n!^ C. 17. 



Length of head 4f, of caudal 5i, height of body about 2/5 of the total length. Eyes — diameter 2/7 of 

 length of head, 2-f diameters from end of snout, and 1-|- apart. Profile from the upper edge of the eye to 

 the snout rather concave. Teeth — five truncated and lobate ones on either side of the upper jaw, and six in the 

 lower. Fins — last dorsal spine as high as the rays, and equal to about 4/13 of the height of the body, the 

 posterior extremity of the soft dorsal and anal fins rather angular. Pectoral as long as the head. Anal as 



2 d 2 



