ICHTHYOLOGY. 215 



T. HArMELA, Forsk. 



Nga-ta-khw6n-klia. (Pa-p;i-drtli, AuJamaus.) 



B. vii. ; D. 127-133; V. 11. 



Lower jaw considcral^ly the lonp;er. Two pairs of largo curved and liarlicd 

 canines in tlie upper jaw, and a pair of similar l)ut smaller ones over the mandilnilar 

 sj-mphysis, and in advance of the snout when the mouth is closed. The anal tin in 

 the shape of small spines, often concealed. Colour grey on the hack, silvery on 

 sides and helly. Fins pale yellow. The upper half of the dorsal dark. Grows to 

 2 feet or so. 



Jcrdon says this species is delicate eating when fresh. 



Cantor describes it as giving off, at certain seasons, a. vivid phosphoric light. 



The Andamans. 



Famih/ Acanthuridse. 



Branchiostegals from 4 to 7. Pseiulobranchite. Body oblong, or elevated and 

 compressed. Teeth on both jaws in a single compressed row. Palate edentulous. 

 A .single dorsal fin. Scales minute. The side of the tail iu adults armed with one 

 or more bony plates or spines. Air-vessel present. 



AcAXTHUiius, Blainville. 



Branchiostegals 5. A movable spine exists iu a groove on the side of the free 

 portion of the tail just below tlie lateral line. 



A. Broad teeth fixed in the jaws. 8 or 9 dorsal spines. 



A. LINE.iTUS, L. 



B, v.; D. VV-T=r; P. 15; V. U A. WV; C. 17. 



Six or seven lobed incisors on either side of upper jaw. Caudal spine lancet- 

 shaped, with a posterior process. Colour, head, and upper two-thirds of body canary 

 yellow, traversed by nine or ten oblicjue blue bands, from the head to the back and 

 tail. Lower third of body reddish-grey. Other blue bands pass upwards and 

 backwards, from the eyo to the body bands. Upper ray of pectoral blue, and inside 

 it a short white line, and an arched white band on the lower half of the pectoral 

 on its lower side. Outer ray of ventral blue, its inner ones red. Caudal with a 

 central semilunar blue band and blue margin. Grows to about 1 8 inches. 



The Andamans. 



A. TKIOSTEGUS, L. 



B. v.; D. ^VH-t; P. 15; V. i; A. Tu^4r=; C. 17. 



Eight lobate incisors on either side of upper jaw, and 9 or 10 on either side 

 of lower. Caudal spine with a sliaiii posterior process. Colour greenish, with a 

 brownish tinge on the back. A vertical dark band along the snout, one through the 

 orbit, four down the body, and two blotches at the base of tail, one above, the other 

 below the lateral line. Fins darkish. 



The Andamans, where common. 



B. Setiform movable teeth dilated at their extremities. 8 dorsal spines. 



A. STOiGosus, Bennett. 



B. v.; D. ^.r^^; P. 17; V. i; A. ^nr^^; C. 17. 



Teeth setiform. movable, and with their outer third dilated and spoon-shaped, 

 with three deep clefts in each. 21 on the upper and 20 on the lower jaw. Caudal 

 spine with a sharp posterior process. Colour, body horizontally lineated with narrow 

 bluish lines on a yellow ground. Many red spots on the head, especially round the 

 eyes. Dorsal and anal fins lineated, and a light median vertical band on the caudal. 



The Andamans. 



