302 ME. C. TATE BEGAN ON THE ^ 



- > 



from the R. Mamoni have been referred by Steindachner to L. rostrata, as a slender 

 variety of that species. 



r" 

 10. OXTLOEICAKIA FKENATA. (Plate XVIII. fig. 2.) 



Loricaria frenata Bouleng. Ann. Mag. Nat. Hist. (7) ix. 1902, p. 69. 



Length of head 4f-5 times in the total length. Breadth of head 1-f— 1-f times in its 

 length, diameter of eye 8^—9-^- times, interorbital width 3j- 3-J times, length of snout 

 If times. Sides of the snout, in the male, with bristles. 32 scutes in a longitudinal 

 series, 14-1 6 + 16-18 ; lateral keels obsolete anteriorly, completely united posteriorly ; 

 abdomen with 2 or 3 series of plates between the lateral ones posteriorly, 3 anteriorly ; 

 anal plate bordered by 3 and these 3 again by 5. Length of first dorsal -ray 3f— 4-| times 

 in the total length ; pectoral spine extending a little beyond base of ventral ; caudal 

 emarginate, the outer rays elongate. Breadth of body at level of last anal ray 

 5-g— 5f times in the distance from the latter to the caudal. Brownish, sides black ; 

 dorsal black, except the upper half of the posterior part of the fin ; anal black 

 anteriorly ; pectorals and ventrals with large black blotches ; caudal black at the 

 base and with a black longitudinal stripe on each lobe. 



Total length 250 mm. 



Eight specimens from N.W. Ecuador. 



14. Farlowella. 

 Acestra (non Dallas) Kner, Denkschr. Alt. Wien, vi. 1853, p. 93; Giinth. Cat. Fish. v. p. 260 



(1864). 

 Farlowella Eigenm. & Eigenrn. Proc. Cal. Ac. (2) ii. 1889, p. 32, and Occ. Pap. Cal. Ac. i. 1890, 



p. 355. 



This genus resembles Oxyloricaria in the dentition and in the absence of an orbital 

 notch, but differs in the more slender body, the position of the dorsal fin, which is 

 opposite the anal, and in the number of fin-rays. The snout has a well-developed 

 rostrum. Dorsal with I 6 rays, anal with I 5, pectoral with I 5--G, ventral with I 4-5. 

 Vertebras 5 + 7 + 23 (in F. Icneri); ribs absent. 



Amazon, Orinoco, and Magdalena Systems. 



Key to the Species. 



I. Abdomen with a median series of plates between the lateral series. 



A. Length of produced part of snout (measured on the ventral surface from the edge of the 

 naked area containing the mouth) 2^-3 times in the distance from its tip to the anus. 

 a. Distance from supraoccipital to base of first dorsal ray 6-6| times in the total length. 

 Diameter of eye 18 times in the length of head ; length of postorbital 



part of head 2| times in that of the produced part of snout . . 1. F. gladius Blgr. 



