FISHES OF THE FAMILY LORICARIIDA. 227 
between the nuchal and posthumeral series. Lower surface of head and abdomen 
completely covered with small granular scales. D. 111; length of base of dorsal equal 
to 1; times its distance from the caudal. A.14. Pectoral spine extending to last 4 
of ventral, Caudal emarginate. Caudal peduncle 3 times as long as deep. lrregular 
dark spots on head and body; fins dark with reticulating light lines. 
Total length 400 mm. 
‘Two specimens (including the type of H. duwodecimalis): Rio San Francisco, Brazil, 
4, ANCISTRUS GIBBICEPS. 
Ancistrus gibbiceps Kner, Denkschr. Ak. Wien, vii. 1854, p. 284, pl. v. fig. 2. 
Liposarcus altipinnis Giiuth. Cat. Fish. v. p. 239 (1864). 
Pterygoplichthys gibbiceps Giinth. t.c. p. 252; Eigenm. & Eigenm, Proc. Cal. Ac. (2) ii. 1889, p. 44, 
and Occ. Pap. Cal. Ac. i. 1890, p. 429. 
Liposarcus scrophus Cope, Proc. Ac. Philad. 1874, p. 136. 
Chelostomus gibbiceps Steind. Denkschr. Ak. Wien, xliii. 1881, p. 114, pl. iv. fig. 1. 
Depth of body 44-42 times in the total length, length of head 23-3 times. Head as 
broad as long and 1} times as long as deep. Diameter of eye 64-72 times in the 
length of head, interorbital width 2-25 times, length of snout 1§ times. Length of 
mandibular ramus 35-33 times in the interorbital width. Snout narrowed anteriorly ; 
supraoccipital with a strongly elevated median ridge; supraorbital edges scarcely 
raised ; temporal plates carinate ; interoperculum armed with a few slender spines, the 
longest less than } the diameter of eye. Scutes spinulose, carinate except on the 
caudal peduncle, 28-30 in a longitudinal series, 5-6 between dorsal and adipose fin, 
12-14 between anal and caudal. Supraoccipital bordered posteriorly by a median 
scute and one on each side; 3-4 series of scutes between nuchal and posthumeral 
series. Lower surface of head and abdomen completely covered with small granular 
scales. D. 1 12-13, the first ray equal in length to the head; length of base of dorsal 
equal to about 1} times its distance from the caudal. A.I 4. Pectoral spine 
extending nearly to middle of ventral. Caudal emarginate, the outer rays produced, 
Caudal peduncle about 3 times as long as deep. Head, body, and fins with rather 
large dark spots separated by reticulating light lines; spots on the head smallest, ou 
the occipital region more or less regulaily radiating. 
Total length 280 mm. 
‘Three specimens: R. Amazon. 
5, ANCISTRUS LITURATUS. 
Ancistrus lituratus Kner, Denkschr. Ak. Wien, vii. 1854, p. 285, pl. v. fig. 3. 
Pterygoplichthys lituratus Giinth. Cat. Fish. v. p. 252 (1864); Eigenm. & Eigenm. Proc. Cal. Ac. 
(2) i. 1889, p. 45, and Oce. Pap. Cal. Ac. i. 1890, p. 433. 
Chetostomus lituratus Steind. Denkschr. Ak. Wien, xliii, 1881, p. 115. 
