454 DK. GUMHER ON THE FISHES OF CENTEAL AMEEICA. 



olive, with an indistinct blackish band running from the orbit to a large black spot on 

 the middle of the side. Dorsal fin with numerous round whitish spots. 



One specimen, 5|^ inches long, was found by Capt. Dow in the Lake of Nicaragua. 



iJescrqition. — The height of the body is contained twice and one-sixth in the total 

 length (without caudal), the length of the head twice and three-fifths. Upper profile 

 of head straight. Head rather longer than high; cleft of the mouth slightly oblicjue, 

 ^\ith the lower jaw rather prominent. Jaws moderately protractile ; the maxillary does 

 not extend to the vertical from the front margin of the eye. Prseorbital as wide as the 

 diameter of the eye, which is somewhat less than the width of the interorbital space, 

 and more than one-fourth of the length of the head. The eye is situated immediately 

 beneath the upper profile of the head, and a little nearer to the end of the operculum 

 than to that of the snout. Scales on the cheek in three or four series ; scales on the 

 opercles large. The dorsal commences vertically above the scapula ; the spinous portion 

 has its upper margin convex ; the spines are slender and long, the fifth and sixtli being 

 the longest, one-half of the length of the head. The soft dorsal and anal have the middle 

 rays somewhat longer than the others, and reaching to about the middle of the caudal ; 

 the soft anal is slightly scaly at the base, the soft dorsal scarcely or not at all scaly. 

 Anal spines shorter but somewhat stronger than those of the dorsal. Caudal slightly 

 (Mnarginate. Pectoral very long, slightly longer than the head, and extending nearly to 

 the end of the anal. Ventral with the outer ray produced into a filament. The distance 

 between the vent and the root of the ventrals is equal to one-third of tlie length of the 

 head. Teeth in the jaws small, cardiform, forming a band, those of the outer series 

 being somewhat larger than the others. 



This species is similar to the Mexican //. helleri, but has a considerably longer 

 pectoral fin, and also less anal rays. 



166. Herds urophtiialmus. (Plate LXXII. fig. 1.) 

 (iuuth. Fish. IV. p. 291. 



D. }-;. A. I. L. lat. 28. L. transv. 512. 

 The fold of the lower lip is continuous in the middle. Scales on the cheek in six 

 scries. The height of the body is contained twice and a half or twice and a quarter in 

 the total length (without caudal), the length of the head nearly three times. Head as 

 high as long ; snout rather elevated, with the cleft of the mouth oblique and with the 

 lower jaw prominent. Prseorbital as wide as the oi'bit; interorbital space flat, wider 

 than the orbit. The eye is nearer to the extremity of the snout than to that of the 

 operculum. Dorsal spines of moderate length and strength, the length of the twelfth 

 being two-fifths of that of the head. The free portion of the tail is higher than long. 

 Anal spines strong and long. The distance between the vent and the root of the ventral 

 is three-fifths of the length of the head. Brownish- or greenish-olive, with seven blackish 

 cross bands, as broad as the interspaces between : the first descending obliquely back- 



