EIGENMANN: the PYGIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 367 



1. Paravandellia oxyptera Riboiro. 



Paravandellia oxij'ptera Ribeiro, I. c. 



Habitat.— Faragnay River near Cacercs. 



Head triangular, eight times in the length including the caudal; D. 12; A. 10; 

 P. 7; dorsal behind the ventrals, partly over anal, both behind the middle of the 

 body; origin of dorsal nearer tip of caudal than base of pectorals; eyes without a free 

 margin, large, two and one-half times in head, equal to snout; maxiUary barbel 

 reaching at most to tip of interopercular spines; pectorals large, falcate, one-fourth 

 longer than head, the first ray longest, the next rapidly graduate, the outer rays 

 longer again; caudal forked, the upper lobe a little the longer; anal similar to the 

 dorsal, under the last rays of the latter. 



White, the eyes black 



The single specimen of this genus and species known, 22 mm. long, was taken 

 in the same locality in which the Ochmacanthus {Gyrinurus) hatrachostoma was 

 caught, among the " pseudo-rhyzomas de Agua-pe" Eichornea azurea, in the margin 

 of the Paraguay River near San Luiz de Caceres. 



Genus XVI". Branchioica Eigenmann." 

 Branchioica Eigenmann, Proc. Am. Phil. Soc, LVI, Jan., 1918, p. 702. 

 Ttjpe. — Branchioica bertonii Eigenmann. 



It is quite possible that this genus will, on direct comparison of specimens, prove 

 a synonym of Paravandellia. It has the same general characters, but comes from 

 the lower Paraguay, while Paravandellia comes from the upper. The present species 

 was taken from a fish, while Paravandellia seems to be free swimming. It is quite 

 possible that teeth will be found in Paravandellia at the end of the maxillary (pre- 

 maxillary?) and on the mandibles when they are examined minutely. Paravan- 

 dellia is said to have the caudal forked, while Branchioica has it subtruncate. 



No nasal or mental barbels, two barbels at angle of the mouth, of which the 

 lower is minute; first pectoral ray not spinous, not prolonged in a filament; gill- 

 openings small, the membrane perfectly confluent with the isthmus; mouth inferior; 

 two series of teeth in the front of the upper jaw, a single series of much smaller teeth 

 laterad of these; maxillary with claw-Hke teeth at its end, just in front of the barbel 

 and entirely concealed; two short series of teeth on the ends of the mandibles, 

 opposite the lateral series of teeth of the upper jaw, the two rami of the mandibles 

 not meeting; opercular and interopercular patches of spines separate from each 

 other; caudal subtruncate. 



^' ffpayxM, TOi = the gills of fishes; Sikcu = to inhabit. 



