206 ACAJSTTHOPTERYGIL 



Variety (? A. Dussumieri, C. and V. x, p. 201) with numerous rather undulating narrow brown bands, 

 the intermediate colour being bluish. Dorsal and anal fins with three or four longitudinal bauds : a light band 

 across the base of the caudal. 



A. mata, has been separated from A. matoides owing to the upper profile of its snout not being so convex, 

 and to the distance of its nostril from the edge of the upper jaw equalling 1/2 (instead of 2/3) the length of 

 the head. The affinities are so great that probably they might with justice be considered varieties. 



Habitat. — Red Sea, seas of India to the Malay Archipelago. The specimen figured (7\ inches in 

 length) was taken at Madras, it is said to attain 18 inches in length. 



8. Acanthurus Celebicus. 



Bleeker, Celebes, hi, p. 761 ; Giinther, Catal. iii, p. 339 ; Kner, Novara Fische, p. 211. 

 ? Acanthurus fuscus, Steind. Verh. z. b. Ges. Wien, 1861, p. 176, t. v.; Giinther, Catal. iii, p, 330 

 (? adult). 



B- v, D. jfzh, P- 16, V. 1/5, A. ^ C. 16. 



Length of head 4f , of caudal 3f , height of body nearly 1/3 in the total length. Eyes— diameter about 

 3f in the length of head. Profile of snout concave. Teeth — about 16 lobate incisors in the upper and 20 in 

 the lower jaw. Fins — last dorsal spine the longest : dorsal and anal rays of about the same height and equal to 

 about 2| in that of the body, the posterior extremity of both fins obtusely rounded. Ventral and caudal lobes 

 pointed. Scales — small, ctenoid, but much larger than in A. matoides or A. mata, there being about 80 rows. 

 Colours — brownish, darkest about the head, lips black, a white ring round the mouth. Dorsal, anal, and ventral 

 fins blackish brown : outer half of pectoral yellowish. Caudal blackish, posteriorly yellowish. 



Habitat. — Malay Archipelago. Kner states that he received a single specimen from Madras. 



9. Acanthurus melanurus. 



Cuv. and Val. x, p. 240 ; Bleeker, Amb. and Ceram, p. 271. 

 Acronourus melanurus, Giinther, Catal. hi, p. 346. 



B. v, D. „*ro P- 15. v - !/ 5 > A - *> C - 16 - 



Length of head 2/7, of caudal 1/5, height of body 1/2 the total length or 2/3 of that of the oval portion. 

 Eyes — diameter 2\ in the length of head, 1 diameter from end of snout (see p. 202). Fins — second dorsal spine 

 longest and strongest, being nearly equal to 1 diameter of the orbit. Caudal cut square or slightly emarginate. 

 Scales — rudimentary or absent. Colours — brownish- white with a black band over the occiput and another over 

 the free portion of the tail. From the whole of the space below the eye and opercle a silvery band passes 

 downwards to the chest. One specimen has a dark mark on the shoulder. 



As the longest specimen I could obtain is only 1-J- inches in length it appears reasonable to believe that 

 this may be the fry of some known form as A. matoides, of which I have small specimens, giving the following : 



1. Acanthurus melanurus, 1+ inches long : 



2. Acanthurus melanurus, \\ 



3. Acanthurus matoides, 2\ 



4. Acanthurus matoides, 2| 



height of body 1/2 of the total length. 

 9X 



55 ^8 55 55 



2J- 



55 ^4 55 55 



55 "2 55 55 



In Cuv. and Val. this species is said to come from Pondicherry and to be obtained up to 2 inches in 

 length. It is also found in the Malay Archipelago. 



Acanthurus melas, Cuv. and Val. x, p. 241, appears to be the same, but having the colours of A. matoides. 

 Habitat. — 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. 



Teuthis hepatus, Linn. Syst. Nat. i, p. 507 ; Gmel. Linn, i, p. 1362. 



Acanthurus hepatus, Bl. Schn. p. 211 ; Cuv. and Val. x, p. 183, pi. 288 ; Bleeker, Floris, p. 325 ; Giinther, 

 Catal. iii, p. 341. 



Acanthurus theuthis, Lacep. iv, pp. 549, 553. 



B. v, D. ^ w , P. 15, V. 1/2, A. &, C. 17. 



Length of head 2/9, of caudal 1/6, height of body 2| in the total length. Eyes — diameter 1/5 of length 

 of head, 3| diameters from end of snout, and 2 apart. Upper profile of head rather convex. Preopercle 

 entire. Teetli^—s\x lobate incisors on either side of both the upper and lower jaws. Fins — last dorsal spine 

 higher than the first ray, beyond which the height of the rays gradually diminishes, the end of the fin being 

 rather angular ; the interspinous membrane scarcely emarginate. Pectoral 4/5 the length of the head. Ventral 

 spine strong, nearly 1/2 as long as the head, its inner ray also spinate at its commencement, but having a 

 bifurcated rayed extremity. Caudal emarginate, its outer rays being prolonged. Scales — the dermal productions 

 are stellate and rough, about 12 rows exist between the lateral-line and the base of the last dorsal spine ; none 

 on the fins. Lancet-shaped spine on side of tail, without any exposed posterior process. Colours— slatey-gray 

 along the back, becoming dashed with brownish-gray along the abdomen. A deep brown band ascends from 

 the posterior-superior angle of the eye, and passing backwards gradually widens untd below the fifth or sixth 



