FISHES OF THE FAMILY LORICARIID®. 210 
anteriorly ; supraorbital edges moderately or slightly raised ; supraoccipital with median 
ridge; temporal plates usually not carinate. Scutes spinulose, usually only those 
posterior to the dorsal carinate, sometimes the anterior scutes also weakly carinate, 
sometimes none of the scutes with distinct keels, 28-30 in a longitudinal series, 
8-9 between dorsal and adipose fin, 14-15 between anal and caudal. Supraoccipital 
margined posteriorly by a median scute and 1 or 2 on each side. Lower surface of 
head and abdomen, in the adult, almost completely covered with small granular scales. 
D. 17, the first ray as long as the head, the last 4 as long; length of base of dorsal 
1§ (young) to 13 (adult) times in its distance from the adipose fin. A. 14. Pectoral 
spine extending to base of ventral or beyond. Caudal strongly emarginate. Caudal 
peduncle 4—5 times as long as deep, broad and flat below, the scutes of the fourth 
series being strongly angulated, forming a ridge which margins the flat lower surface, 
Dark spots on head, body, and fins, those on the dorsal usually arranged in two series 
between each pair of rays. 
Total length 470 mm. 
Nineteen specimens (including the type of the species): Brazil to Colombia. 
10. PLEcosToMUS ALATUS. 
Hypostomus alatus Casteln. Anim. Am. Sud, p. 41, pl. xx. fig. 1 (1855). 
Plecostomus alatus Giinth. Cat. Fish. v. p. 234 (1864) ; Liitk. Vid. Selsk. xii. 1875, p. 144. 
Plecostomus francisct Liitk. Overs. Dan. Selsk. 1873, no. 3, p. 30; Vid. Selsk. xn. 1875, 
p- 148. 
Depth of body about 5 times in the total length, length of head 3} times. Depth 
of head 1} times in its length, breadth of head 1} times, length of snout 13-1? times, 
diameter of eye 64 times, interorbital width 22 times. Length of mandibular ramus 
24 times in the interorbital width. Snout broad, rounded ; supraorbital edges not 
raised ; supraoccipital with low median ridge; temporal plates not carinate. Scutes 
spinulose, not carinate, 27-28 in a longitudinal series, 9 between dorsal and 
adipose fin, 15 between anal and caudal. Supraoccipital entirely bordered posteriorly 
by a single scute. Lower surface of head and abdomen, in the adult, almost 
completely covered with small granular scales. D.17; the first ray as long as the 
distance from its base to the tip of snout; length of base of dorsal equal to its 
distance from the middle of the spine of the adipose fin. A.I 4. Pectoral spine 
extending to anterior third of ventral. Caudal emarginate, the inner rays % the 
length of head, the outer much produced. Caudal peduncle 3} times as long as deep. 
Brownish, with yellow spots on head, body, and fins. 
Total length 300 mm. 
‘Two specimens (including the type of the species): Araguay, San Francisco, and 
das Velhas Rivers. 
