382 • MR. C. TATE REGAN ON [Apr. 10, 



1 . Macrodon trahira Spix. 

 " Guabin." 



" Much appreciated as an article of food, although rather bony ; 

 they are purchased readily by the labouring classes. 



" A very small specinien'(30 mm.) Avas caught at Oumuto ; it was 

 skimming along the top of the water when captured. Examples 

 of this size can vibrate the pectoial fins with extreme rapidity ; 

 they often rest as if asleep, hence the name ' Dormeuse.' 



" Colour : greenish, a more or less distinct blackish longitudinal 

 band and irregular cross-bars ; vei-tical fins with series of dark 

 spots." 



Hah. Brazil ; Guiana ; Venezuela. 



2. ErYTHRINUS UNITiENIATUS Spix. 

 '* Yarrow." 



" Found all over the island in mviddy streams. 

 " Colour ; greenish or olivaceous ; sometimes a dark longitudinal 

 lateral stripe ; fins pink." 



Ilab. Brazil ; Guiana ; Venezuela. 



Genus Corynopoma. 



Slevardia Gill, Ann. Lye. N, York, vi. 1858, p. 424. 



Coryno2wma Gill, t. c. p. 425 ; Giinth. Cat. Fish. v. p. 287 

 (1864). 



Nematopoma Gill, t. c. p. 428. 



This genus appears to be allied to Tetragonopterics, from which 

 it differs in the more posterior position of the dorsal fin, the 

 absence of an adipose fin, and in the curious sexual characters. 



3. Corynopoma rush. (Plate XXII. fig. 3.) 



Stevardia cdbipinnis Gill, Ann. Lye. N. York, vi. 1858, p. 425. 



Corynopoma riisei Gill, t. c. p. 426 ; Giinth. Cat. Fish. v. p. 287 

 (1864) ; Lutken, Vid. Med. 1874, p. 223. 



Corynopoma veedoni Gill, t. c. p. 427 ; Giinth. 1. c. 



Nematopoma searlesii Gill, t. c. p. 429. 



Corynopoma albipinnis Giinth. I.e. 



Corynopoma searlesii Giinth. t. c. p. 288 ; Liitk. 1. c. fig. 



Body compressed, subfusiform, the depth 3-3| in the length, 

 the length of head 4^-4|. Snout much shorter than eye, the 

 diameter of which is 2^-21 in the length of head and nearly equal 

 to the interorbital width. Mouth small, very oblique, the maxillary 

 nearly vertical, just in front of the eye. Teeth compressed, with 

 strong median cusp and 1 to 3 smaller cusps on each side, in 2 series 

 in the upper jaw, 1 in the lower. Opex-culum, in the female, with 

 a short pointed projection ; in the adult male with a long, slender, 

 curved process terminating in a compressed expansion at the level 



of the dorsal fin. Scales 38-44 ^g, 5 or 6 between lateral line and 

 root of ventral ; lateral line complete. Dorsal 9-11, commencing 



