4. NASEus. 353 



rather broad, white edge. Yoiing specimens with a white ring round 

 the tail. 



East Indian Archipelago. Polynesia. 



a-c. Six to ten inches long : stuffed : protuberance just conspicuous. 

 Aneiteum. From Mr. Macgillivray's Collection. 



*• A convex and compressed liump above the snout in adnlt specimens. 



7. Naseus tuberosus. 



Renard, i. fig. 79 ; Valcnt. iii. p. .386. fig. 119, & p. 499. fig. 478. 



Naso tuberosus, Lacep. iii. p. 111. pi. 7. fig. 3. 



Acanthurus uasus, Shaw, Zool. v. p. 876. pi. 51. 



Naseus tuber, Cuv. ^- Val. x. p. 290. 



? Naseus tonganus, (Quo;/ &• Gaim.) Cuv. Sf Val. x. p. 292. 



Naseus vlammgii, Cuv. i)' Val. x. p. 293 ; BJeck. Batav. p. 472. 



T) 5-6 A 2 



27-30" 27-28' 



The anterior profile of the snout is convex, in mature specimens 

 very prominent, like a crest. Teeth slightly compressed, small, 

 tapering, about twenty on each side of the upper jaw. Brown, with 

 black (blue) dots or short vertical Unes ; fins blackish, the vertical 

 with white margins. 



From Mauritius to Pol}Tiesia. 



a. Twenty-two inches long : stuffed. Ceylon. From Dr. Sibbald's 

 Collection. — Caudal spines very strong ; crest very convex. 



h. Young. Coram. From Madame Ida Pfeiffers Collection. — 

 Caudal spines none ; profile of the snout slightly convex. 



c, d. Adult and young: stuped. Aneiteum. From Mr. Macgilli- 

 vray's Collection. 



€. Fine specimen. 



/. Half- grown : stuffed. Old Collection. 



g, h. Adult : skins. From the Collection of the Zoological Society. 



Young specimens have the dorsal spines much more slender and 

 longer than adult ones. The form of the caudal fin is subject to 

 great variation, as in many fishes of this and other families, some 

 individuals ha\-ing it nearly truncated behind, whilst in others the 

 lobes are produced into long filaments. N. tonganus is founded on 

 a specimen which is said to have been immaculate. N. tuberosus is 

 a species, in which the height of the body, the profile of the snout, 

 the length and number of the dorsal spines, the size of the caudal 

 spiniferous laminae, the form of the caudal fin, and, as it appears, the 

 colours, are variable, and chiefly dependent on age. 



*** Head without honi or hump in mature specimens. 



8. Naseus lituratus. 



Valent. iii. p. 371. fig. 77; Itemtrd, i. 23, 128. 



Harpui'us lituratus, Forst. Descr. Anim. eel. Licht. p. 218. 



Acanthurus lituratus, Bl. Sclin. p. 216. 



harpurus, Shair, Zool. iv. p. 381. 



Aspisurus elegans, Riipp. Atl. Fische, p. 61. taf. 16. fig. 2. 



VOL. Ill 2 A 



