1. CH.«TODON. .3 



First Group. CH^TODONTINA. 

 1. CH^TODON*. 



Chsetodon, (Artedi) Cuv. IRkgne Anhn. ; Cuv. ^~ Val. vii. p. 3. 



Body much compressed and elevated. One dorsal, without any 

 notch, with the Spinous and soft portions similarly developed ; none 

 of the spines elongate. Muzzle short or of moderate length. No 

 teeth on the palate ; pra;operculum entire or shghtly serrated, with- 

 out spine. Scales generally large or of moderate size. Six branchio- 

 stegals. Au'-bladdcr sometimes with horns or with two divisions. 

 Intestinal tractus with many convolutions ; pyloric appendages iii 

 moderate number. 



Seas between the Tropics. 



I have divided the numerous species of this genus as follows, in 

 order to facihtato their determination : — 



I. Scales large or of moderate size, not exceeding fifty-five transverse 

 series. 



A. More than ten dorsal spines. 



1. More than three anal spines, p. 4. 



2. Three anal spines. 



a. One or more of the dorsal rays elongate, p. 6. 



b. None of the dorsal rays elongate. 



a. A large round black or white spot— 

 aa. On the dorsal fin, p. 8. 

 bb. On each side of the body, p. 11. 

 /3. Without a romid black or white spot. 



aa. Body with distinct longitudinal bands (not stripes), p. l.'i. 

 bb. Body with broad cross-bands, p. 17. 

 cc. Body mthout bands, with stripes or spots, or uniform. 

 aa. Ventrals dark-coloiu-ed, p. 21. 

 ^^. Ventrals light-coloured. 



* Caudal with a black cross-band or crescent, p. 23. 



* Caudal ^■ith a fine black cross-streak, p. 28. 



* Caudal with a blackish margin, p. 30. 



* Caudal without dark transverse streaks, generally uni- 



fonn, p. 31. 



B. Ten dorsal spines or less, p. 34. 



n. Scales small, in sixty or more transverse series, p. 34. 



* 1. Cli.'v?todon mertensii, Cuii. tf- Val. vii. p. 47. — Hab. ? 



2. Rcnard, ii. 56. 239 ; Falent. f. 407. — ChaBtodon principalis, Cuv. ^f Val. 



vii. p. 81. — East Indies. 



3. Ch.-Btodon parallelus, Gronov. Si/si. cd. Gray, p. 70. — East Indies. 



4. Cluutodon limulatus, Quoy ^~ Gaim. Voy. Freyc. Zool. p. 381. — Sandwich 



Islands. 



5. Ch.ttodon, no. 7, Arfcdi, Sj)ecics, p. 95. — Hab. ? 



G. Chsetodon layardi, Blyfh in Kelaarf, Prodrom. Fann. Zcylan. Append. 

 p. 50. — Ceylon. 



b2 



