260 MEMOIRS OF THE CARNEGIE MUSEUM 



premaxillaries minute and free from each other, the maxillary a slender curved 

 bar, its posterior end curved upward, slipping under the preorbital, not reaching 

 to below the nares; the mandibles out of proportion, nearly 2.5 times longer, the 

 articulation under the anterior part of the orbit. About eight tricuspid teeth 

 inserted in the lip some distance from its anterior margin. No teeth in the lower 

 jaw. 



Cheeks narrow, covered by the second suborbital, there being a naked area 

 only under its anterior angle. 



Scales hard, in regular series on the sides, the uppermost series of the sides 

 meeting rather irregularly behind the occipital process; in the angle between these 

 series and the dorsal there are first a few median scales and then two series of 

 scales which end at the dorsal; fins all naked; axillary scale of the ventral more 

 than half as long as the fin; humeral process continued as an adnate adipose ridge. 

 Scales all highly iridescent, without lines. 



Origin of dorsal about an orbital diameter nearer the snout than to the caudal; 

 dorsal pointed, the first rays about 4.5 in the length, the penultimate less than 

 half as long as the longest; adipose fin small; caudal very deeply forked, the lobes 

 pointed, a little over one-fourth of the length; anal very small, emarginate, the 

 tip of the highest ray about reaching the tip of the last; origin of ventrals under the 

 posterior part of dorsal, reaching half-way to first or sometimes to last anal ray; 

 pectorals reaching nearly half-way to tip of ventrals. 



Straw-colored, upper caudal lobe light orange, ranging to yellow below. 

 Highly iridescent, a dark streak along the shoulder just behind the opercle; bases 

 of scales of the upper part of the sides dark. 



This species is abundant about the sand-bars in the lower Essequibo. 



Subfamily Curimatin^e. 

 Curimatopsis Steindachner. 

 Curimatopsis Steindachner, "Ichthyologische Beitrage," v, 1876, 33. 

 Type, Curimatopsis macrolepis Steindachner. 



This genus has heretofore not been taken outside of the Amazon basin. 

 Teeth none; mouth small, very oblique, cyprinodontiform; tongue long, 

 narrow, free; lateral line developed on a few scales only. 



119. Curimatopsis macrolepis Steindachner. 

 Curimatus (Curimatopsis) macrolepis Steindachner, "Ichthyologische Beitrage," 

 v, 1876, 33 (Tabatinga; Manacapuru; Mouth of the Rio Negro). 



