106 



U.S. NATIONAL MUSEUM BULLETIN 202 



Vol. 3 



Description. — Dorsal fin rays IIT-ii,26; anal rays ii,24; pectoral 

 rays i,13; branched caudal rays 5 + 5; gill rakers on first gill arch 33, 

 long, slender, pointed; scale rows 52; teeth in upper jaw 8, lower 

 jaw 8, inclined toward median line, slightly protruding, notched. 



Depth of body 2.0; length of head 2.65; both in standard length. 

 Snout 1.3; diameter of eye 6.1; least depth of caudal peduncle 4.6; 

 length of pectoral fin 3.35; length of longest dorsal ray 3.2; length of 

 longest anal ray 3.5; length of caudal fin 3.2; interorbital width 4.35; 

 all in length of head. Angle of snout profile 29 degrees, snout profile 

 straight. 



Table 131. — Comparison of number of dorsal and anal rays of 2 species 



of Canthidermis 



Nostrils set in shallow groove, below this a deeper groove before 

 eye; upper orbital rims prominent, interorbital slightly convex; en- 

 larged platelike scales behind branchial opening just above pectoral 

 axil; a patch of enlarged, rectangular scales on cheek about 6 rows 

 deep and 8 to 10 scales wide, these scales larger than those of body; 

 about 7 rows of short antrorse spines on caudal peduncle; scales of 

 anterior side of body, back, and belly smooth, not bearing short spine 

 or enlarged tubercle; soft dorsal and anal fins low, rounded, not ele- 

 vated anteriorly; caudal fin sub truncate, slightly emarginate; pectoral 

 fin short, rounded. 



Color in alcohol.— Hesid and body light greyish brown with scat- 

 tered small indistinct irregular patches of darker greenish brown, 

 dorsal part of back darker than sides and belly; faint straight yellow- 

 ish white line running from rictus to vertical from eye; similarly 

 colored line across throat just behind chin connecting two side lines; 

 lips pale greyish; soft dorsal fin light olive brown; anal fin pale yel- 

 lowish white; caudal fin color of body, ground color on median por- 

 tion, upper and lower edges and narrow distal margin brown. 



SUFFLAMEN CHRYSOPTERA (Bloch and Schneider) 



Plate 137 



Balistes chrysopterus Bloch and Schneider, Systema ichthyologiae . . ., p. 266, 

 1801 (based on B. armi of Lacepfede, Histoire naturelle des poissons, vol. 1, 

 p. 382, pi. 18, fig. 2, 1798; type locality, Indian Ocean). 



