140 TELEOSTEI. ACASTHOPTEBTGIT. 



than the longest ray, and equal to T \ or | of height of body. 

 Pectoral A aslong as head. Caudal lunate, ^-rudimentary 

 and cycloid on h?ad, small and ctenoid on body ; about twenty 

 rows "between lateral line and last dorsal spine. Lancet-shaped 

 spine with a sharp posterior process. Least depth of free portion 



Fig. 54. Acanthurus triostegus. 



of the tail equal to about li- diameters of the orbit. Colour - 

 greenish, with a brownish tinge along the back. One vertical dark 

 band along the snout, a second through the orbit, four down the 

 body, and one over the base of the caudal fin, the last being in the 

 form of two rounded blotches, one above, the other below the 

 lateral line. Fins stained darkish. 



Hal. Seas of India, the Malay Archipelago, and beyond. Com- 

 mon at the Andaman Islands ; rare at Madras. 



896. (5.) Acanthurus tennentii. 



Acanthurus tennentii, Giinther, Catal. iii, p. 337 ; Day, Fish. India, 

 pp. 204, Suppl. p. 788. 



D. 9/25. P. 17. V. 1/5. A. 3/22. C. 17. 

 Length of head 4J, of caudal 5|, height of body 2| in the total 

 length. Eyes diameter 3| in length of head, 2 diain. from 

 end of snout. Nostrils the length of head from end of snout. 

 Teeth eight lobate incisors on either side of the upper, and eight 

 on either side of the lower jaw. Fins last dorsal spine nearly 3 

 the height of the body, and about equal to the rays : posterior 

 extremity of the soft dorsal and anal rather angular. Pectoral as 

 long as head. Caudal emarginate. Scales about fourteen rows 

 between lateral line and base of last dorsal spine. A posterior 

 process to the lancet-shaped spine. Colour brown, caudal with a 

 broad white posterior edge, having a dark base behind it. The 

 skin in the British Museum has a dark ring on the shoulder which 

 appears very like an ink-mark ; the pectoral seems to have been 

 tinged with yellow in its posterior half on the lower side. 

 Hab. Ceylon and Burma. 



