66 



equal to the greatest height, which occurs at the same point. The 

 length of the head is one-sixth (0.17) of total length, and its greatest 

 width equals that of the body. The orbit is circular, and its diameter 

 equals the interorbital space, which is half the length of the head. The 

 snout is very short, equaling one-sixth the length of the head ; the lower 

 projects far beyond the upper jaw. The interorbital space is deeply 

 concave. The dorsal and anal fins begin at a point slightly behind the 

 middle of the body, and are nearly alike in shape and in the length of 

 the base and of the longest rays. The pectorals measure three- fifths 

 (0.58) of the total length, extending nearly to the base of the caudal fin. 

 The first ray is half as long as the second, which projects far beyond the 

 margin of the membrane in a spine-like process; the third ray equals 

 the second, while the fourth is much longer. The membrane between 

 the second and third rays is deeply, between the third and fourth slightly, 

 emarginated. The rays succeeding the fourth gradually decrease in* 

 length. The ventrals begin slightly in advance of the middle of the 

 body, in length equaling a third (0.31) of total length. The five poste- 

 rior rays are bifid nearly to the base. The tips of ventral and pectoral 

 fins are equidistant from the snout. The upper lobe of the caudal 

 measures two-thirds the length of the lower lobe. 



Color. — Back bluish, shading into the silvery white of the belly; five 

 broad lateral transverse bands. The snout transparent white. Two 

 yellow spots upon the nape. Pectorals and ventrals black at base and 

 at margin, and with broad, irregular bands and blotches of black and 

 dark blue; where unspotted, clear, colorless, and transparent. Caudal 

 lobes each with a terminal spot of black ; the lower with spot of same 

 color on its outer margin half-way from the body to its extremity. 



Extreme length, 0™ .073 100 



Body: 



Greatest height 12 



Greatest width 19 



Height at ventrals 10 



Height of tail behind dorsal fin 06 



Head: 



Length 17 



Distance from snout to nape 15 



Greatest width 12 



Width of interorbital area 10 



Length of snout 03 



Eye: 



Diameter 08 



