458 DE. GtJNTHEE ON THE FISHES OF CEXTEAL AMEEICA. 



fourths. The eye occupies the middle or nearly the middle of the length of the head. 

 Scales on the cheek in four or five series. Base of the dorsal fin scaly. The lenqfh of 

 the eighth dorsal spine is more than one-third of that of the head. The depth of the free 

 portion of the tail is scarcely more than its length. Greenish or yellowish, with about 

 six indistinct dark cross bands ; that below the fourteenth dorsal spine with a large 

 black blotch below the lateral line ; sometimes a black spot on the upper half of the 

 base of the caudal. 



Two male specimens were collected by Capt. Dow in the Lake of Managua; the 

 larger, 8 inches long, has the labial lobes and black caudal spot ; the smaller is 7 inches 

 long, and, without doubt, of the same species. The female sex is unknown. 



Description. — Head as high as long ; snout rather elevated, with the cleft of the 

 mouth oblique, and the lower jaw rather prominent. Upper profile very concave. 

 Teeth in narrow bands, those of the outer series enlarged, with brown tips. The 

 maxillary does not reach nearly to the vertical from tlie front of the orbit ; preeorbital 

 as wide as the orbit, being contained very slightly more than four times in the length 

 of the head. Interorbital space flat, much wider than the orbit. The eye is situated 

 immediately below the upper profile, slightly nearer to the extremity of the snout than 

 to that of the operculum. Opercles scaly, the scales being larger than those on the 

 cheeks ; suboperculum with one series of scales. The soft portions of the anal and 

 dorsal fins with a series of small scales between the rays at their base. Dorsal spines 

 of moderate strength, the length of the eighth to twelfth being more than one-third of 

 that of the head. Points of the soft anal and dorsal reaching to the middle of the 

 caudal. The free portion of the tail is scarcely higher than long. Caudal rounded, its 

 length being one-fifth of the total. Anal spines strong and long. Pectoral rounded, 

 reaching to the fourth anal spine ; outer ventral ray produced. The distance between 

 the vent and the root of the ventral is three-sevenths of the length of the head. 

 Coloration as described above. 



172. Herds citrinellus. (Plate LXXI. fig. 1.) 



Giinth. Proc. Zool. Soc. 1864, p. 153. 



D. ^^. A. g^. L. lat. 30. L. transv. 6/13. 

 The fold of the lower lip is continuous in the middle. The height of the body is 

 contained twice and a fifth in the total length (without caudal), the length of the head 

 twice and seven-eighths ; the free portion of the tail is conspicuously deeper than long ; 

 nape of the neck very convex ; interorbital space broad, its width being two-fifths of the 

 length of the head. Snout not obtuse ; scales on the cheek in four series. The first 

 dorsal spine is inserted above the upper end of the gill-openmg. Dorsal and anal 

 spines slender, the eighth or tenth of the dorsal fin being two-fifths of the length of 

 the head. Pectoral nearly as long as the head. Lemon-coloured, either nearly uni- 



