138 TELEOSTEI. ACANTHOPTEBIGII. 



892. (1.) Acanthurus lineatus. 

 Cha?todon lineatus, Gmelin, Syst. Nat. i, p. 1240. 

 Acauthurus lineatus, Day, Fish. India, p. 203 (see syuon.). 



Sciveyah, Ceylon. 



D. 8-9/28-31. P. 15. V. 3/5. A. 3/27. C. 17. 



Length of head 5| to 5g, of caudal 3, height of body 3 in the 

 total length. Eyes diameter 4| in length of head, 3 to 3| diam. 

 from end of snout, and 1| apart. Profile from dorsal fin to snout 

 obtuse. 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, upper 

 lobe the longer. Scales about 8 rows between lateral line and 

 base of last dorsal spine. Lancet-shaped spine with a posterior 

 process. Least depth of the free portion of the tail e<jual to | 

 the length of the head. Colour head and upper two-thirds of 

 body canary-yellow, traversed by nine or ten more or less oblique 

 blue bands from the head to the back and caudal fin ; lower third 

 of body reddish grey. Two or three blue bands pass down the 

 summit of the head and the anterior edge of the eye towards the 

 snout ; 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 grey margin. Pectoral having its upper ray 

 blue, and just internal to* it a white line ascending halfway 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 seinilunar blue band in its middle and a blue postei-ior 

 edge. 



Bennett observed 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. 



Hab. Seas of India to the Malay Archipelago ; common at the 

 Andamans in December and January up to 10 inches in length. 



893. (2.) Acanthurus leucosternum. 



Acanthurus leucosternon, Bennett, P. Z. S. 1832, p. 183 ; Day, Fish. 

 India, p. 203 (see synon.). 



D. 9/29-30. P. 16. V. 1/5. A. 3/27-28. C. 17. 

 Length of head 4f , of caudal 5, height of body about 2| in the 

 total length. Eyes diameter 3 in length of head, 2| diain. 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, on either side of upper jaw, and six in lower. Fins last 

 dorsal spine as high as the rays, and equal to about T \ of height of 

 body posterior extremities of soft dorsal and anal fins rather 

 angular. Pectoral as long as head. Anal as high as soft dorsal ; 

 caudal emarginate. Scales very small, rough and rudimentary on 



