294 MEMOIRS OF THE CARNEGIE MUSEUM. 



Habitat. — Sierra dc C6rdol)a, near Cruz del Eje, Argentina; Caiza, Bolivian 

 Chaco. 



The following is from Boulenger's description of specimens up to 62 mm. long: 

 " Head 4.66-5; D. 8-9; A. 6; eye three times in interorbital, a little nearer snout 

 than to opercle; maxillary barbel reaching pectoral; caudal peduncle twice as long 

 as high; distance between origin of dorsal and caudal two and one-half times in the 

 distance between dorsal and snout; outer pectoral ray prolonged; origin of ventrals 

 equidistant from snout and tip of caudal, or a little nearer the latter; caudal trun- 

 cate, or slightly emarginate. A dark lateral band." 



6. Pygidium spegazzinii licrg. 

 Pygidium spegazzinii Berg, An. Mus. Nac. Buenos Aires, V, 1897, p. 267; Eigen- 



mann, Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 399. 



Habitat. — Rio de Cachi, Province de Salta, northern Argentina, 2,500-2,800 m. 



Known only from the types, 29 specimens, the largest of which is 95 mm., in 

 the National Museum of Buenos Aires. 



Head 6.5-7.5 in the length with the caudal; D. 11 (3 + 8); A. 9 (3 + 6); eye 

 much nearer snout than to edge of opercle; nasal barbel extending beyond the eye, 

 maxillary barbel short and broad ; gill-membrane without free margin at the middle ; 

 teeth in many series; interopercular spines few, in three or four rows, the sixth to 

 eighth in the lower row moderate in size; opercular spines also few and minute; body 

 verrucose; pectoral obliquely rounded, its first ray not prolonged; anal inserted 

 under posterior part of dorsal; caudal subtruncate or rounded. 



7. Pygidium borellii (Boulenger). 

 Trichomycterus borellii Boulenger, Boll. Mus. Zool. Anat. Comp. Univ. Torino, 



XII, 1897 (Mission d'Aguairenda; Tala; Lesser); Ann. & Mag. Nat. Hist. 



(7), IX, 1902, p. 336 (Palmira, Rio Mendoza). 

 Pygidium borellii Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 



1910, p. 400. 

 Pygidium schmidti Berg, An. Mus. Nac. Buenos Aires, V, 1897, p. 266 (Rio de 



Belen, Prov. Catamarca, Argentina); Eigenmann, I. c, p. 399. 



Habitat. — Mission d'Aguairenda, Bolivian Chaco; Tala and Lesser, Province 

 Salta, northern Argentina; Rio de Belen, Province Catamarca, northern Argentina; 

 Palmira. 



Reaching a recorded length of 110 mm. 



Head 5.35-5.5; D. 10; A. 7; eye very small, in middle of the head, three times 

 in the interorbital; body compressed, caudal peduncle one and one-half times as 



