24. BUYCoN. 335 



and four-fifths in the total length (without caudal), the length of the 

 head four times or four times and one-fourth. An indistinct hu- 

 meral spot ; each caudal lobe with a bi-oad bhick longitudinal band, 

 the bands confluent on the root of the fin ; a blackish band along 

 the base of the anal. 

 British Guiana. 



a-c. Three of the typical specimens. British Guiana. Presented 



by Sir E.. Schomburgk. 

 (J-e. Fine specimens. Essequibo Eiver. Purchased of Mr. Ehrhardt. 

 /. Adult : skeleton. Surinam. 



5. Brycon orthotsenia. 

 D. 11. A. 29. Y. 8. L. lat. 53. L. transv. 10/7. 



The height of the body is contained thrice and one-third in 

 the total length (without caudal), the length of the head nearly five 

 times. Intermaxillary teeth in three series ; lower jaw without inner 

 lateral series of teeth. The origin of the dorsal fin is behind the root 

 of the ventral, and a little nearer to the base of the caudal than to 

 the extremity of the snout. The pectoral does not extend to the 

 ventral. Lateral line uninterrupted, the muciferous tubes of each 

 scale being much ramified. The free portion of the tail, behind the 

 adipose fin, is rather higher than long. Greenish, shining silvery ; 

 a straight, broad, deep-black band runs along the middle of the free 

 portion of the tail and along the middle caudal rays. Caudal fin 

 only slightly emarginate. 



Brazil. 



a. Skin, 16 inches long. River Cipo. Presented by Ch. Cumberland, 

 Esq. — Vernacular name : MatriYixim. 



0. Brycon brevicauda. 



D. 11. A. 26-27. V. 8. L. lat. 55. L. transv. 11/7. 



The height of the body is contained twice and three-foiu-ths or 

 twice and four-fifths in the total length (vrithout caudal), the length 

 of the head thrice and three-fourths. Intermaxillaiy teeth in 

 thi'ce rather irregular series ; the lateral portion of the inner series 

 of the mandible terminates anteriorly close to the median teeth. 

 The origins of the dorsal and ventral fins are in the same vertical 

 line, ecpially distant from the extremity of the snout and from the 

 root of the caudal. The pectoral does not extend to the ventral. 

 BeUy compressedj'^ut not trenchant. Silvery, with a shining line 

 along each series onBcales ; an indistinct humeral spot ; each caudal 

 lobe with a broad bla?k longitudinal band, the bands confluent on the 

 root of the fin ; anal blackish, with a light band along its middle. 



(I. Adult: skin, 11 inches long. Rio Jocintins. Purchased of Mr. 



Gardiner. 

 ^-c Half-grown, 41 inches long. River Capin. Purchased of Mr. 



Stevens. 



