SOUTH AMERICAN NEMATOGNATHI. 305 



band of teeth deepest in front, ta- 

 pering backward, the teeth villiform, 

 depressible, the inner series several 

 times as large as the outer ; teeth of the 

 mandible similar. 



Gill-membranes confluent with the skin of the isthmus. 

 Gill-rakers short, slender, 8 + 14. 



Distance of dorsal spine from snout 3J in the length. 

 Dorsal spine strong, posterior margin smooth, its outer 

 margin with strong hooks turned to right and left; first 

 ray l-? } - in the head; distance of the adipose from the dor- 

 sal fin 2 in the length. Adipose fin short and high. 



Caudal fin forked, 5i in the length. 



Anal fin long, its origin equidistant between base of 

 caudal and angle of mouth. 



Ventral fins joined to the body on their inner margin, 

 the first ray reaching origin of the anal fin, 1| in head. 



Base of pectorals horizontal, the spine 2| in the head, 

 slender, flexible, its outer margin smooth, its inner mar- 

 gin finely serrate, the longest ray 1| in the head. 



Light brownish, darker above. 



Head 4; depth 6J; Br. 10; D. I, 6; A. 43; V. 7. 



One specimen .30 m. Rio Puty; Orestes St. John. 



239, Ageneiosus armatus. 



Silurus militaris Bloch, Auslandische Fische, parts, 19, pi. 362, 1794; 

 Bloch & Schneider, "Syst. Ichthyol. 379, 1801" (not Linnaeus). 



Ageneiosus mllitaris Bleeker, Silures de Suriname, 80, 18S4 (Sur- 

 inam). 



Auchenipterus militaris Steindachner, Fisch-fauna des Magdalenen 

 Stromes, 19, 1878. 



Ageneiosus armatus Lacepede, Hist. Nat. Poiss. v, 122, 1803 (Suri- 

 nam). 



Habitat: Surinam. 



The combination Silurus militari* is a synonym of 

 Osteogeneiosus militaris (Linnseus), and the name milita- 

 ris cannot be retained for this species. 

 20 



