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PROCEEDINGS OF THE NATIONAL MUSEUM. 



vol. 40. 



orbital 3.35, raised, somewhat convex; bony projections over eyes 

 and on forehead moderately developed; preopercle weakly denticu- 

 late; teeth small, close-set; gill membranes narrowly joined to the 

 isthmus; peritoneum white. 



Scales moderate, regular in arrangement; lateral line complete, 

 moderately arched, parallel with contour of body; about 44 trans- 

 verse rows of scales between opercle and base of caudal; vertical fins 

 scaled, scaly sheath not extending to tip of dorsal spines, the line of 



Fig. 2.— Heniochus singulabius. (From the type. Three-fifths natural size.) 



demarcation very distinct; head scaled; lips, upper surface of snout, 

 and opercular flap naked. Scales broad, basal margin truncate, apical 

 margin rounded; sculpturing of scale like that in Clixtodon; circuli 

 numerous; basal radial folds well developed, few in number; hastate 

 structures composing radial lines on apical margin very distinct. 



Dorsal fin inserted anteriorly, distance from tip of snout to origin 

 of dorsal 2,06 in length; first to third dorsal spines relatively short, 



