266 Fretp Museum or Natura History — Zoétocy, Vor. X. 
flap; first dorsal ray with its tip produced, its length 1.1 to 1.4 in head, 
the tips of first dorsal rays reaching slightly past those of the last rays 
when the fin is deflexed; pectoral spines produced, their tips reaching 
to or past middle of ventrals, their length .7 to .9 in head; ventrals 1 
to 1.2; adipose fin long, without trace of spine; caudal peduncle deep, 
1.7 to 1.9 in head; last anal ray to caudal 1.5 to 1.7 in head; caudal 
emarginate, the outer rays produced. : 
Color brownish mottled with darker; base of anal and dorsal black; 
a faint black bar at base of caudal rays; base of first rays of anal usually 
with a black spot. 
This species was quite abundant in the Rio Cana at Cana. Longest 
specimen 130 mm. This species ranges farther north than any of the 
other species of the family. 
Family V. Pygidiide. 
Small fishes with naked bodies, usually villiform teeth, remote nares, 
skull covered with skin and muscles, no adipose fin, and a rudimentary 
air bladder enclosed in the lateral processes of the coalescent vertebra. 
The family is represented by a number of genera, but only one species 
is known to inhabit Panama. 
15. Genus Pygidium Meyen. 
Pygidium Meyen, Reise in Peru, I, 1835, 475 (type Pygidium fuscum 
Meyen). 
Body elongate, subterete; mouth terminal or subterminal; teeth in 
bands in both jaws; maxillary with 2 pairs of barbels; a single pair of 
nasal barbels; eyes superior; dorsal over or behind ventrals; its origin 
over or in advance of origin of anal; without spine; no adipose fin; opercle 
and preopercle with small spines; body naked; gill-membranes nearly 
free from the isthmus or forming a free fold across it. 
Small fishes inhabiting mountain streams from Central Chili to 
Panama and southeastern Brazil and central Argentina. 
21. Pygidium striatum Meek & Hildebrand. 
Pygidium striatum Meek & Hildebrand, Field. Mus. Nat. Hist. Pub., 
Zool. Ser., X. 1913, 78 (Rio Cana, Cana, Panama). 
Head 4.9 to 5.75; depth 6.35 to 7.35; D. 8; A. 6. 
Body elongate; head depressed; body posteriorly compressed; snout 
broad, its length 2.08 to 2.9 in head; eye very small, wholly superior, 
