30 U.S. NATIONAL MUSEUM BULLETIN 202 Vol. 2 



lateral line 3 ; scale rows below lateral line 7 ; scale rows around caudal 

 peduncle 14. 



Body depth 3.6 to 4.0; head length 2.8 to 3.0; length of caudal 

 peduncle 3.6 to 4.1; length of longest pectoral rays 4.1 to 4.7; all in 

 standard length. Eye, highly variable with size, comparatively 

 smaller in the larger specimens, 4.9 to 7.1; length of upper jaw 2.3 to 

 3.4; depth of caudal peduncle 3.0 to 3.3; length of snout 1.7 to 2.0; 

 width of interorbital 3.8 to 5.1; all in length of head. Eye in snout 

 2.4 (in smallest specimen) to 4.2 (in largest). Width of interorbital 

 in eye, variable, 0.5 to 1.0. Length of barbel in length of head 1.1. 

 Gill rakers, including rudiments, 6 to 8+1+22 to 24, total 29 to 32 

 in 16 Marshall Islands specimens; longest raker about 1 to 1.2 in long- 

 est filament. 



Teeth of upper and lower jaws stout, blunt tipped, widely spaced, 

 and in a single row; no teeth on vomer or palatines; scales on caudal 

 fin, absent on dorsal and anal fins; cheek and opercle scaled; barbels 

 long, reach end of head or to base of pelvic fins in most specimens; 

 first dorsal spine minute, second dorsal spine almost as long as third, 

 flexible at tip; peritoneum transparent; lateral line complete; scales 

 ctenoid, with 5 to 6 radii in anterior field; last rays of soft dorsal and 

 anal fins somewhat elongate. 



Color in alcohol. — Body and head pale to light tan in most of the 

 smaller specimens, and tan with some dusky in the larger ones. Fins 

 are transparent in smaller specimens, transparent to slightly dusky 

 in larger ones. Barbels are colored light tan. Body, head, and fins 

 of 2 smaller specimens darker, dusky to brown. Light blotch on 

 dorsal portion of the caudal peduncle posterior to soft dorsal fin 

 present in about 40 percent of the specimens from the Marshall 

 Islands. This spot is conspicuously developed in 2 specimens, faint 

 in 2 specimens, questionable in 2, and not perceptible in all others; 

 when present, its size is variable, usually extending half distance from 

 end of base of soft dorsal to procurrent caudal rays, in smaller speci- 

 mens, to about three-fourths of this distance, in larger ones. 



Color in life. — A brownish blue and a yellow color phase have been 

 observed in life by Strasburg who recently collected in the southern 

 Marshall Islands. These color phases correspond with the dusky 

 (dark) and light color phases observed in some of our smaller preserved 

 specimens. It cannot be determined at this time whether these 

 phases are associated with size and maturity, or sex, or reproduction, 

 or whether perhaps two distinct forms are involved. All our larger 

 specimens have a uniform dusky to tan coloration. 



The following color description taken in life at Wake Island by 

 John E. Randall, University of Miami, from a specimen 313 mm. in 

 length (USNM 167602) tentatively referred to this species: Body 



