80 PROCEEDINGS OF THE ACADEMY OF [1897. 



MONACANTHIDJE. 



Monacanthus sulcatus Hollurd. 



Monacanthus sulcatus Hollard, Ann. des Sci. Nat., 4th Series, Zool,, torn. 

 2, p. 363, pi. 14, fig. 11; Giinther, Cat., VIII, 239. 



Three specimens, 3* to 4 inches long. 

 Head 3|, depth 2i, eye 3 ; D. 1-33 ; A. 33 ; C. 12. 

 Profile between the dorsal fins but little oblique, the origin of the 

 second dorsal being scarcely higher than the anterior fins. Upper 

 and lower profiles of head nearly straight, forming an angle of a 

 a very little over 60°. Dorsal spine over hinder part of orbit, its 

 length equal to the distance from end of snout (not tip of teeth) to 

 middle of eye, shorter than caudal, longer than the longest dorsal or 

 anal rays. It has two rows of strong barbs on the outer hinder 

 edges, about a dozen in each series, and an anterior double series of 

 small barbs. The rudiment of a second dorsal spine is covered by 

 the skin. Ventral spine short, half length of eye, movable, granu- 

 lose, with four barbs at tip, two pointing forward and two backward. 

 The pubic bone projects beyond the dermal flap, granulose, provided 

 with eight barbs, four at base pointing forward, and four at tip, the 

 two larger pointing forward and the two smaller backward. Dorsal 

 slightly anterior to anal. Rays of pectoral and posterior rays of 

 dorsal and anal webbed only for the basal third of their length, the 

 web on dorsal and anal becoming higher anteriorly. Caudal rays 

 very coarse. All rays of all fins more or less spinulose at base. Gill- 

 opening oblique, partly under hinder margin of eye, in front of 

 pectoral. Length of tail, measured from anal, f of its depth. Scales 

 very small, each with a single curved spine. Each spine curves 

 over and nearly touches the next succeeding, thus forming longitu- 

 dinal lines which often intersect. The scales of the ventral flap are 

 scattered and armed with three straight spinelets. Scales on head 

 and as far back as pectorals with several minute spinelets, a patch 

 in front of orbit with a single point directed forward. A rather in- 

 distinct line of scales, each with a pair of straight spinelets, extends 

 backward from the upper part of'the eye about half or two-thirds of 

 the way to the dorsal fin, then curves downward to or below the axis 

 of the body, and then extends to the caudal. Color in alcohol: a 

 dark spot about size of eye under anterior part of soft dorsal; proba- 

 bly a few other small spots on upper part of body ; edge of ventral 

 flap black. 



