380 



BLACKISH ACANTHURUS. 



Acanthurus Nigricans. A. nigricans, subtus subargenteus, eauda 



utrinque aculeata. 

 Blackish Acanthurus, subargenteous beneath, with a spine on 



each side the tail. 

 Chaetodon nigricans. Ian. Block, t. 203. 



Of nearly the same size with the preceding, but 

 with the front sloping more suddenly downwards 

 from the origin of the dorsal fin : colour dusky, or 

 blackish brown, with the under parts inclining to a 

 subargenteous cast : scales rather small : dorsal 

 and anal fin scaled at the base : gill-covers un- 

 armed : on each side the tail a strong and sharp 

 spine, as in the former species : tail nearly entire, 

 or but slightly lunated: teeth broad and crenulated 

 or lobed on the edges : native of the Indian, 

 American, and Arabian seas, and said to grow to 

 the length of two feet, and to be esteemed for the 

 table. 



MILITARY ACANTHURUS. 



Acanthurus Militaris. A. corpore rhombeo-ovato fusco, cauda 



utrinque aculeata. 

 Brown Acanthurus, with rhombic-ovate body, and strong 



spine on each side the tail. 



Length about five inches : shape rhombic-ovate : 

 head sloping suddenly downwards : colour brown : 

 scales extremely small : teeth denticulated or ere- 



