BIGENMANN: PIMELODELLA AND TYPHLOBAGRUS 251 
Habitat—Paraguay Basin. 
10125 I. U. M., type, 126 mm., Bahia Negra, Paraguay, Anisits. 
10200 I. U. M., part, 50 mm., Villa Rica, Anisits. 
6959a C. M., 135 mm., Puerto Suarez, Paraguay, May 7, 1909. Haseman. 
6960a-f C. M., 63-86 mm., Laguna Ypacary, Arequa, Paraguay, April 7, 1909. 
Haseman. 
6972a C. M., 112 mm., near Berlin, Bolivia, Rio Mamoré, Sept. 14, 1909. Hase- 
man. 
Very similar to P. gracilis but the adipose distinctly shorter, the tip of the 
anal extending to or beyond the tip of the adipose. 
Head 4; depth 5; D. 1.6; A. 10-12; eye 3.5-4.5 in the head; interorbital 3.75—4; 
maxillary barbel to within an orbital diameter of the caudal or middle of caudal; 
adipose 3-3.66 in the length. Pectoral spine equal to length of head less opercle, 
with 5-9 recurved hooks near tip in front, these followed by about 30-40 tubercles, 
most of which are antrorse; 11-21 recurved teeth along most of the posterior 
margin; dorsal spine equal to snout and half of the eye. Caudal deeply forked, 
the lower lobe broader and longer, 3.5 in the length; the tip of the anal extends 
to or beyond the vertical from the tip of the adipose. A well-developed lateral 
band, heaviest behind the gill-opening. The maxillary barbel extends to near the 
base of the caudal and may extend beyond its tip. Eye 4 + in the head; inter-. 
orbital equal to the eye. The adipose is 3-3.66 in the length. 
Kry To tHe TRANS-ANDEAN SPECIES OF PIMELODELLA." 
a. Upper caudal lobe about equal to head in length; pectoral spine with thorns for more than two- 
thirds its length. 
b. Basal four-fifths of pectoral spine with very strong hooks on its posterior face, the hooks of the 
distal half longer than the width of the spine at its base. Dorsal spine with a few teeth on 
its posterior face. Adipose fin 4.25-5 in the length, pectoral spine very little longer than 
snout and eye, maxillary barbel reaching to somewhere about the ventrals. Head 4.25; 
Glyn HD); IOs UA. WNP es parce mcs oh coer e soos ns one ooma umm S or 29. grisea Regan. 
bb. Basal three-fourths or four-fifths of the pectoral spine with hooks along its posterior face, the 
hooks less than the width of the spine, posterior face of dorsal spine rough; adipose fin 34-32 
in the length, pectoral spine about equal to snout and eye. Maxillary barbels reaching some- 
where about middle of adipose, shorter in the young. Head 4.8, depth 5.5; D. 1.6; A. 12; 
a sharply defined lateral band...................................80. modesta (Gtinther). 
bbb. Basal two-thirds of the pectoral spine with eight (6-8 fide Steind.) hooks; posterior face of 
dorsal spine smooth; adipose fin 2.66 in the length; pectoral spine very little less than snout 
and eye; maxillary barbel reaching the last third of the ventrals; head 4.33; depth 5; D. 1.6; 
A. 12; no sharply defined lateral band........................ 31. yuncensis Steindachner. 
14 This account is extracted from the MS. of my forthcoming monograph on the fishes of Colombia. 
It was prepared in collaboration with Mr. Homer G. Fisher. 
