1. ACANTHURUS. 327 



I. With nine or eight (seven) dorsal spines, with broad Jixeu incisors, and 



with Jive soft ventral rays. 



A. With black cross-bands on the head and body. 



1. Acanthurus triostegus. 



Seba, iii. 25. 4 ; Emsell, i. pi. 86. 



Chastodon triostegiis, L. Syst. i. p. 463. 



Acanthurus triostegiis, Bl. Schn. p. 215 ; Cuv. Sf Val. x. p. 197 ; Bleek. 



Verhand. Batav. Genootsch. xxiii., Teuth. p. 13 ; Jetiyns, Voy. Beagle, 



Fishes, p. 75. 

 Ilarpurus fasciatus, Forst. Descr. Anim. ed. lAchL p. 216. 

 Acanthurus zebra, Lacep. iv. p. 546. pi. 6. fig. 3. 

 Chjetodon zebra, Lacip. iii. pi. 25. fig. 3. 



couagga, Lacfp. iv. p. 727. 



Acanthurus hirudo, Benn. Ceyl. Fishes, p. 11. pi. 11. 



Teuthis australis, Gray in King^s Survey of the Coasts ofAiistr.n. p. 435. 



Acanthunis subaimatus, Bemi. Whaling Voy. ii. p. 278. 



^•^.- ^-h- ^-l/S- Vert. 9/13. 



The height of the body is one-half the total length (the caudal fin 

 not included). The upper jaw with seven lobate incisors on each 

 side ; caudal spine small, without posterior projecting process. The 

 upper profile of the snout is concave. Caudal fin subtruncated, 

 Eeddish-violet, with five blackish-brown transverse bands, the an- 

 terior of which passes through the orbit ; another streak of the same 

 colour along the median line of the snout ; two brown spots, one 

 above the other, on the end of the tail. 



From Mauritius to Polynesia and New Zealand. 

 a-d, e. Fine specimens. Amboyna. Purchased of Mr. Frank. 

 /. Half-grown : bad state. Celebes. Purchased of Mr. Frank. 

 g, h. Adult : bad state. Malayan Archipelago. Presented by Sir 



J. Richardson. 

 {. Adult : skin : bad state. Sandwich Islands. 

 k. Fine specimen. Aneiteum. From Mr. Macgillivray's Collection. 

 /. Adult. West coast of Australia. From Captain King's Collection. 



— Type of Teuthis australis, Gray. 

 m, n, o,p, q. Adult and half-grown. 

 r. Adult: stuffed. 

 s. Adult : skeleton. From the Collection of the Zoological Society. 



Skeleton. — The skull has a very peculiar physiognomy, from the 

 shortness of its cranial portion and the elongation of its fi'ont part, 

 in which, however, the jaw-bones do not participate. In general 

 form it is somewhat compressed, elevated, triangular. The crown 

 of the head is very short and convex, with the occipital crest 

 moderately developed ; the interorbital space is broad and flat. The 

 frontal bones and the prjeorbital are prolonged, the bones situated 

 before them being very short. Turbinals well developed, united on 

 the median line. The jaws are formed as in Teuthis : the maxillary 

 and intermaxillary are firmly and immoveably joined together, and 

 the latter has its posterior processes extremely short. The lower jaw 

 is broad and very short. Palatines very short ; all the bones of the 

 tympanic cavity are well ossified, and of rather lai'ge size; the epitym- 



