444 DE. aUNTHER OX THE FISHES OF CENTRAL AMERICA. 



right one; the prseorbital tapers posteriorly, has the anterior margin finely serrated, 

 and covers the maxillary, so that only a very narrow portion of it is visible on the side 

 of the snout. Eyes hidden anteriorly and posteriorly by a broad adipose membrane. 

 Nostrils rather distant from each other, the posterior situated nearer to the orbit than 

 to the extremity of the snout. The space of the chin, between the mandibles and the 

 interopercula, is elongate cuneiform. The second dorsal and the anal are enveloped 

 in small scales. There are twenty-three scales between the snout and the anterior 

 dorsal. The second dorsal spine is longer than the first, and more than half as long as 

 the head. The tenth, eleventh, and twenty-fifth scales of the lateral line correspond to 

 the extremity of the pectoral fin and to the origins of the two dorsal fins. The root of 

 the pectoral is above the middle of the body; and the ventral is inserted somewhat 

 nearer to the pectoral than to the spinous dorsal ; pectoral shorter than the head ; 

 caudal deeply emarginate. Silvery, axil of the pectoral blackish. 



We have received examples of this species from Dutch and British Guiana; Mr. 

 Salvin collected two tine examples in the Chagres River. 



I formerly considered it possible that the fish described by Hancock might be identical 

 with M. hrasilimsis ; but having now received examples, I have convinced myself that it 

 is a distinct species. 



123. Agonostoma microps. (Plate LXX. fig. 1.) 

 Gunth. Fish. iii. p. 462. 



D. 4|J. A. g. L. lat. 43. L. transv. 12. 



Broad bands of villiform teeth in the jaws, on the vomer, and the palatine and 

 pterygoid bones. The height of the body is contained five times in the total length, 

 the length of the head four times and a half; the latter is more than the distance 

 between the origins of the two dorsal fins ; snout much longer than the eye. Upper 

 lip thick, protruding anteriorly. The maxillary extends to, or beyond, the vertical 

 from the anterior margin of the eye. The interorbital space is convex. The anterior 

 dorsal commences midway between the snout and the base of the caudal fin. 



Mr. Salvin has collected specimens of this species (of which we have given a detailed 

 description, I. c.) in the Rio Guacalate. 



124. Agonostoma nasutum. (Plate LXX. fig. 2.) 



Aqonostoma nasutum, Gunth. Fish. iii. p. 463. 



Dajaus^ elongatus, Kner & Steindachner, Sitzgsher. bayer. Ak. Wiss. 1863, p. 232; and Abliandl. 

 bayer. Ak. Wiss. 1865, p. 6, Taf. 1. fig. 2. 



nasutus, Kner & Steindachner, /. c. p. 8. 



D. 4|J. A. I L. lat. 42. L. transv. 12. 

 Rather narrow bands of villiform teeth in the jaws, on the vomer, and palatine bones. 

 The height of the body equals the length of the head, and is one-fifth of the total. 



' See Zool. Record, ii. p. 192. 



