236 



PACU OF GUIANA. 



Myletss ? pacu. 



PLATES XX. AND XXI. MALE AND FEMALE. 



Pacu of the Natives. Schomh. Dratvings, No. 101, A. ; No. 101, B. 

 Male and Female. 



'• Snout short, and terminates In a small mouth ; 

 lips fleshy ; two rows of teeth on the inter-maxillary 

 bone ; teeth in sockets, nine in the lower and nine 

 in the upper jaw, resemble much the molar teeth 

 of sheep, chiefly the three middle ones ; there is, 

 liowever, likewise an acute tooth in the lower and 

 four in the upper jaw, the upper ones forming a 

 double row with the molar-like teeth. Body ellip- 

 tical, rather compressed; belly almost trenchant, 

 and obscurely serrated; fins supported by cartila- 

 ginous articulated rays ; head covered with a naked 

 skin ; nose double ; body descending suddenly to- 

 wards the mouth ; air-bag of moderate size ; lateral 

 line distinct and curved. Colour a brownish red, 

 with several blackish spots in the vicinity of the 

 dorsal fin; there are likewise four fasciae of the 

 same colour towards the tail, two below and two 

 above the lateral line. The rays of the fins are 



