302 MR. C. TATE REGAN ON THE 
from the R. Mamoni have been referred by Steindachner to JL. rostrata, as a slender 
variety of that species. - 
10, OxyLoricaRIA FRENATA. (Plate XVIII. fig. 2.) 
Loricaria frenata Bouleng. Ann. Mag. Nat, Hist. (7) ix. 1902, p. 69. 
Length of head 43-5 times in the total length. Breadth of head 13-14 times in its 
length, diameter of eye 83-9} times, interorbital width 3}-3} times, length of snout 
12 times. Sides of the snout, in the male, with bristles. 52 scutes in a longitudinal 
series, 14-16 + 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 33-43 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 
54-52 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. Ak. Wien, vi. 1853, p. 93; Giinth. Cat. Fish. v. p. 260 
(1864). 
Farlowella Figenm. & Eigenm. Proc. Cal. Ac. (2) ii. 1889, p. 32, and Oce. Pap. Cal. Ac. i. 1890, 
p. 350. 
‘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 5-6, ventral with I 4-5. 
Vertebre 5+7-+23 (in PF. kneri); 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) 24-3 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. 
