Dec. 28, 1916. FisHes or PANAMA— MEEK AND HILDEBRAND. 253 
and the female, which we designate as the type, was taken in the Rio 
Calobre, tributary of the Rio Bayano. 
Differing from A. chagresi principally in the higher fins. The male 
specimen has but 6 rays in the dorsal, but this may be due to an injury, 
as the fin apparently was mutilated sometime during the fish’s career. 
9. Genus Lasiancistrus Regan. 
Lasiancistrus Regan, Proc. Zool. Soc. London, XVII, Pt. III, r 04, 224 
& 237 (type Chetostomus heteracanthus Ganther). 
Body broad anteriorly; caudal peduncle posteriorly compressed; 
head without prominent ridges, the plates not carinate; scutes on back 
and sides spinulate but not carinate; lower surface of head and abdomen 
naked; margin of snout with granules and bristles; premaxillaries 
quite as long as the dentaries; mandibular ramus notably shorter than 
interorbital width; preopercle more or less freely movable, armed with 
rather strong spines, the apex of each spine bent outward and forward; 
D. I, 7; adipose fin well developed. 
10. Lasiancistrus planiceps (Meek & Hildebrand). 
Ancistrus planiceps Meek & Hildebrand, Field Mus. Nat. Hist. Pub., 
Zoél. Ser., X, 1913, 79 (Rio Tuyra, Boca de Cupe, Panama). 
Head 2.6 to 2.9; depth 5.3 to 6.9; D. I, 7; A. I, 5; lateral scutes 24 or 
25. 
Body broad, low, depressed anteriorly; caudal peduncle posteriorly 
compressed; dorsal profile nearly straight from eyes to dorsal; ventral 
surface anteriorly broad and flat; head low and very wide; snout moder- 
ately acute, its margin with granules and bristles, 1.6 to 1.85 in head; 
eye 7 to 10; interorbital 2.25 to 2.45; mouth of moderate width, the 
lips expanded, forming a sucking disc; the margin of lower lip nearly 
smooth, with a very small barbel, shorter than eye, on its lateral margin 
behind angle of mouth; teeth small, bifid and curved inward near the 
tips; premaxillaries a little longer than the dentaries; the mandibular 
ramus 3 to 4 in interorbital width; interopercle with about 20 spines 
which vary greatly in length among individuals; sculpture of head 
without carinations and without ridges, except for a broad, low ridge 
on median line of snout; scutes on back and sides spinulate, the first 
median scute behind occipital anteriorly convex, broadest at median 
line of back; 7 scutes between dorsal and adipose, 11 or 12 between anal 
and base of dorsal; lower surface of head and abdomen completely naked; 
dorsal fin high, the posterior rays when deflexed failing to reach adipose 
by 1 or 2 rows of scutes, its spine longer than snout and eye, 1.3 to 1.5 
