28 FISHES FROM BRAZIL 



slight differences from the description published by Dr. Eigenmann (South 

 American Nematognathi, p. 198), and add a few variations. 



The occipital crest reaches at least ^ of the distance from its base to 

 to the dorsal spine. The eye is contained from 6^ to 7 3^ times in the 

 snout; 3^2 to 4 times in the interorbital space; and 14 to 16 times in the 

 lengtli of the head. The maxillary barbel often reaches to the tip of the 

 pectoral, and the postmental is usually coterminous with it, or sometimes 

 is a trifle shorter. The upper lobe of the caudal bears a long filament, 

 variable in length, but often as long as the entire body. The lower lobe 

 is in one or two case filamentous and twice the length of the head, though 

 usually it is but little produced or half that length. The vent is only 6 

 diameters of the eye from the anal. The entire side of the body is not 

 reticulated and porous, but it bears a lateral band which is about half as 

 wide as the interorbital space under the dorsal, grows a little wider anteriorly 

 and tapers to a point posteriorly. The head is contained from 3}4- to 3^ 

 times in the length. 



In life it is a strikingly beautiful fish, with metallic golden red, cop- 

 pery and silvery reflections. 



95. Tsenionema platynema (Boulenger) . 



A single specimen, 22 inches in length, was collected at Para. It is 

 referred to this species, though in many of its characters it resembles as 

 well Tcenionema steerci Eigenmann and Bean, making it appear probable 

 that the two are identical, as suggested in the original description of the latter 

 species. The eye is contained 4 times in the interorbital space, 14 times in 

 the snout, 20 times in the head, the adipose dorsal is 3 times as long as 

 deep, and the ventral and pectoral are equal in length. All of these char- 

 acters are as in T. platynema. The length of the head is 3 times as long as 

 deep, and the length of the first dorsal ray is contained 1^^ times in the 

 head as in T. steerei. The depth of the body is 6^/2 times in the length, and 

 the depth of the caudal peduncle is 2 times in its length. The fins and the 

 sides are bright yellow in alcohol ; its colors in life were not recorded. 



Platypogon, new genus. 



This genus is related to Brachyplatystoma, but has the barbels with 

 their inner edges bearing a thin dermal membrane, and has not the char- 

 acteristic small eye and flat, depressed snout. The teeth are freely movable 

 and in broad bands. On the premaxillary, and to a less degree on the 

 mandible, they grow longer posteriorly and point backward. The palatine 

 and vomerine teeth form a continuous band. The fontanel doe* not extend 



