38. XIPHORHAMPHTTS; 355 



length (with the caudal), the length of the head one-fourth ; the 

 length of the cleft of the mouth is nearly one-half of that of the 

 head. The origin of the dorsal fin is in the second third of the total 

 length (without caudal). A black humeral and caudal spot. 

 Brazil, Guiana. 



3. Xiphorhaniphus microlepis. 



Hydrocyon microlepis, Schomb. Fish. Guian. i, p. 247. pi. 24 (25 a, 



Hydrocyon ? armatus). 

 Xiphorhamphus microlepis, Mull. § Trosch. Hor. Ichth, i. p. 18. 



D. 11. A. 31-33. L. lat. 100-110. 



The height of the body is one-sixth or one-seventh of the tow. 

 length (with the caudal), the length of the head somewhat less than 

 one-fourth ; the length of the cleft of the mouth is more than one- 

 half of that of the head. The origin of the dorsal fin is in the second 

 third of the total length (without caudal). A black spot on the base 

 of the caudal fin. 



Guiana. 



a-6. Young. British Guiana. Presented by Sir B. Schomburgk. 

 c. Adult. Essequibo. From Mr. Ehrhardt's Collection. 



4. Xiphorhamphus feroz. 



Gilnth. Ann. $ Mag. Nat. Hist. 1863, xii. p. 443. 



D. 11. A. 25-26. V. 8. L. lat. 95. 



Maxillary with two distant canine teeth in its upper portion. The 

 height of the body is contained four times and two-thirds in the total 

 length (without caudal), the length of the head thrice and a half; 

 the length of the snout is equal to the distance of the posterior pra> 

 opercular margin from the middle of the eye. The diameter of the 

 eye is more than one-half of the length of the snout, and one-fifth 

 of that of the head. The maxillary extends a little beyond the hind 

 margin of the orbit. The origin of the dorsal fin is midway between 

 occiput and base of the caudal ; the anal fin commences immediately 

 behind the dorsal ; caudal deeply forked. The pectoral does not 

 extend to the ventral. A large blackish blotch behind the gill- 

 opening ; the middle caudal rays orange-coloured, with a round black 

 spot at the base. 



Essequibo. 



a-b. From 6 to 7 inches long : types of the species. From Mr. 

 Ehrhardt's Collection. 



/3. All the maxillary teeth of equal length. 



5. Xiphorhamphus pericoptes. 



Mull. 8f Trosch. Hor. Ichth. i. p. 32. taf. 5. fig. 1. 



D. 11. A. 33. V. 9. L. lat. 74. 



All the maxillary teeth are equally small. The height of the. body 



2 A 2 



