143 PISHES. 



the other internal, the three intermediate ones branching as usual. They 

 have five branchial rays, and a horizontal spine before the dorsal. The 

 styloid bones of their shoulder lengthen out in a curve, so as to unite 

 themselves by their extremities to the first interspinal of the anal*. 

 Numerous species are found in the Indian Ocean -j\ 



Acanthurus, Lacep. and Bl. — Harpurus, Forst. 



These fishes, vulgarly called Surgeons, have the teeth trenchant and 

 notched; a strong moveable spine on each side of the tail, that is as sharp 

 as a lancet, and inflicts severe wounds on those who carelessly handle 

 these fishes; hence their vulgar name. They inhabit the hot parts of 

 both oceans J. 



The dorsal of some species is very highS. 



Some have a sort of brush composed of stiff hairs, before the lateral 

 spine || . 



In others again the teeth are deeply notched, or pectinated on one side^[. 

 The 



Piuonurus, Lacep. 



Only differ from the preceding genus in the armature of the sides of the 

 tail, which consists of a series of fixed, horizontal, and trenchant blades**. 



Naseus, Commers. — Monoceros, Bl. Schn. 



Have, like the preceding, the sides of the tail armed with fixed trenchant 

 blades: but the teeth are conical, and the front projects in a kind of horn 

 or knob above the muzzle; but four rays in the branchia?, and three soft 

 ones in the ventrals; the skin resembles leather jf. 



* Geoff. Phil. Anat. I, 471, and pi. ix, f. 108. 



f Thelitis javus, L., Gronov. Zoophyl. pi. VIII, f. 4; — Siganus stellat/is, Forsk.; — 

 Amphac. punctatus, Bl. Sclin., or Acanthurus meleagris, Shaw; — Burn brunneus, 

 Commers., Lacep. V, 421 ; — Siganus rivulatus, Forsk.; — Amphac. nebulosus, Quoy and 

 Gaym. Zool. Voy. Freyein. p. 369; — Centrogaster fuscescens, Houttuyn; — Chatodan 

 guttatus, Bl. 196; — Amph. marmoralus, Quoy and Gaym. Voy. Freyein. Zool. pi 62, 

 f. 1 and 2; — Amph. mc.gniahac, lb. f. 3; — Centrogaster argenlatus, Houtt., and seve- 

 ral others to be described in our Icthyology. 



X Chalodon chirurgus, Bl. 208; — Thelitis hepaius, t.j Seb. Ill, xxxiii, f. 3; — Ac. 

 glauco pareius, Cuv., Seb. III. xxv, 3, which appears to be the true Chatodon nigricans, 

 L.; — Chert, triostegus, Brousson., Dec. Icth. No. 4, or Acanthure zebre, Lacep., which 

 is also his Chat, zebre, III, xxv, 3; — Ac. guttatus, Bl., Schn.; — Ac. suiUtis, Cuv., Re- 

 nard, I, pi. xiv, f. 82;— Chat, lineattis, L. ; Seb. Ill, xxv, I;— Chat. Achilles, Brous- 

 sonnet; — Chat, meta, Russ. 82; — Chat, sohal, Forsk., of which Lacep. has very im- 

 properly made a genus under the name of Apisurus ; — Ac. slriatus, Cuv.; Paningu, 

 Renard, pi. 1, f. 8; — Ac. argente, Quoy and Gaym. Voy. Freyein., p. 63, f. 3; — Chat, 

 nigrqfuscus, Forsk.; — Chat, nigricans, Bl. 203, which is not that of Linnaeus. 



§ Ac. velifer, Bl. 427. 



|| Ac. scopas, Cuv., Renard, I, pi. xi, 101. 



^[ Ac. clemdoii, Cuv., a new species. 



** Prionurc microUpidote, Lacep. An. Mus. IV, p. 205; — Acanthurus scalp f Urn, 

 Langsdorf. 



■ft Naseus fron/icornis, Cuv., Lacep. Ill, vii, 2, BL, Schn., pi. 42, Hasseq., it. pal. 

 332 ;—Nas. tandock, Ren. I, i v, 23 ; Valent. 5 1 8 ; — Chat, unicornis, Forsk., differ from 

 our first species.— Was. brevirostris, Cuv., Ren. I, xxiv, 130; — Nas.tumifrons, Cuv., 

 badly drawn, Ren. I, 178;— Kas. incoruis, Cuv., Ren. I, f. 128, and not so'wcll, f. 117, 



