214 MR. C. TATE REGAN ON THE 
a naked area behind the mouth and one at the base of each ventral. D.1I 7, the first 
ray as long as the head, and reaching the adipose fin when laid back, the last less 
than half as long; length of base of dorsal equal to its distance from the posterior 
part of the spine of the adipose fin, A,1I4, Pectoral spine extending nearly to 
middle of ventral. Caudal emarginate. Caudal peduncle 2} times as long as deep. 
Uniformly olivaceous, the fins dusky. 
Total length 240 mm. 
One specimen from Paraguay. 
‘This species is very closely allied to P. datirostris, differing in the shorter and 
deeper body, the longer barbel, the first dorsal ray reaching the spine of the adipose 
fin when laid back, and the longer pectoral. 
15, PLECOSTOMUS MACROPS. 
Plecostomus macrops Eigenm. & Eigenm. Proc. Cal. Ac. (2) i. 1888, p. 170, and Occ. Pap. Cal. 
Ac, i. 1890, p. 410. 
Depth of body 44 times in the total length, length of head 5} times. Head as 
broad as long, its depth 1% times in its length, diameter of eye 5% times, interorbital 
width 24 times, length of snout 1$ times. Length of mandibular ramus twice in the 
interorbital width, Barbel a little shorter than the diameter of eye, Snout broad, 
rounded; supraorbital edges raised; supraoccipital convex, elevated posteriorly, but 
without distinct median ridge; temporal plate not carinate. Scutes spinulose, not 
carinate, 26 in a longitudinal series, 7 between dorsal and adipose fin, 14 between 
anal and caudal. Supraoccipital entirely bordered posteriorly by a single scute. 
Lower surface of head and abdomen covered with small granular scales, except for 
naked areas behind the mouth and at the base of each ventral. D.1 7, the first ray 
as long as the head, not reaching the adipose fin when laid back, the last 3 as long. 
Length of base of dorsal equal to its distance from tip of spine of adipose fin. A. I 4. 
Pectoral spine extending to anterior + of ventral. Caudal emarginate. Caudal 
peduncle 5} times as long as deep, Uniformly olivaceous. 
Total length 250 mm, 
One specimen (type of the species) from the Rio das Velhas, Eastern Brazil. 
16. PLecosroMUS GARMANI, sp. n. (Plate X. fig. 1.) 
Plecostomus lima (non Liitk,) Eigenm. & Eigenm, Occ. Pap. Cal, Ac. i. 1890, p. 409. 
Depth of body 6 times in the total length, length of head 34 times. Depth of head 
]} times in its length, breadth of head 1} times, length of snout 14 times, diameter ot 
eye 64 times, interorbital width 3} times. Length of mandibular ramus 14 times in 
the interorbital width. Barbel a little shorter than diameter of eye. Snout broad, 
rounded; supraorbital edges not raised; supraoccipital slightly convex, without 
