SOUTH AMERICAN NEMATOGNATHI. 51 



lary band strongly curved; vomerine 

 teeth in two oval patches joined to 

 the larger patches of the palatines; 

 mandibulary band of teeth separated 

 in front, the outer margins, if con- 

 tinued forward, forming an angle at 

 the symphysis. 



Maxillary barbels reaching beyond 

 base of pectorals; mental barbels 

 reaching about | toward the gill-opening, the post men- 

 tals to the gill-opening in one specimen, a little be- 

 yond in the other. 



Gill-membranes forming a broad free margin across 

 the isthmus. Gill-rakers 3+4. 



Pectoral pore minute; humeral process pointed behind. 



Distance of dorsal from snout 2| in the length, the 

 dorsal spine covered with a membrane, its outer margin 

 granular, "its height 1| in the head, the first soft ray 

 1| the length of the fin. Distance of adipose fin from 

 the dorsal 3|-4 in the length, the fin adnate, longer than 

 the dorsal. 



Caudal lunate, the upper lobe longer, somewhat fal- 

 cate, 4^-5 in the length. 



Anal fin twice as long as high, the highest ray 2-21 

 in the head. 



Ventrals short and broad. It in the head. 



Pectoral spine covered with a membrane, li-ll in head. 



Taght brown, becoming nearly white below, the sides 

 freckled, fins reddish. 



Head 4-4|; depth 5-6; D. I, 6; A. 22. 



24. Tachisurus peruvianus. 



Galeichlhijs peruvianus Littken, Videusk. Meded. 1874, 205 (Callao); 



Steiudachuer, SB. Ak. Wien, Ixxiv, 1876, Ichthyol. Beitr. iv, 



34 (Callao; Altata; Pauania). 

 Tachisurus peruinnnus Eigenm. & Eigeum. Proc. Cal. Acad. 2d. Ser, 



vol. i, 1888, 140 (Callao). 

 Habitat: West coast tropical America. 



