246 MR. C. TATE REGAN ON THE 
E. Interorbital width 32-33 times in the length of head. 
Dorsal with I 9 (rarely I 10) rays, the last # as long 
as tiie first . 5. 2 » « © «imines .- «=: = MOQGROstmNmeneaRnReDIIES 
1. fCIATOSTOMUS LOBORHYNCHUS. 
Chetostomus loborhynchos Tschudi, Fauna Peruana, Pisce. p. 26, pl. iv. (1845). 
Chetostomus loborhynchus Giinth. Cat. Fish. v. p. 250 (1864). 
Depth of body about 5} times in fhe total length, length of head about 3 times. 
Head a little broader than long. Diameter of eye 7-8 times in the length of head and 
1 times in the interorbital width. Interoperculum with 11 spines. Fold of the upper 
lip with median prolongation. 25-26 scutes in a longitudinal series. Dorsal longer 
than high, the length of its base equal to ¢.the length of head. D.1 8-10. A. 13. 
Pectoral spine extending a little beyond the base of ventral. 
‘The typical example about 145 mm. in total length. 
Andes of Peru. 
2. CH#TOSTOMUS MACULATUS, sp. n. (Plate XIV. fig. 4.) 
Depth of body 54-6 times in the total length, length of head 2 times. Head as 
broad as long and 24 times as long as deep. Diameter of eye about 9 times in the 
length of head, interorbital width 23-23 times, length of snout 14 times. Length of 
mandibular ramus slightly less than the interorbital width. Interoperculum armed 
with 7 or 8 spines. 25 scutes in a longitudinal series, 7 between dorsal and adipose 
tin, 12 between anal and caudal. D.17; the first ray equal to 3-3 the length of head, 
the last $-3 as long; length of base of dorsal less than its distance from the spine of 
the adipose fin, which is preceded by a keel formed by 3 or 4 scutes. A. I 3. 
Pectoral spine not extending to base of ventral. Caudal peduncle 2% times as long as 
deep. Olivaceous, with rather large light spots on head and upper part of body; fins 
spotted or clouded with darker. 
‘Total length 65 mm. 
‘lwo specimens from Rozmaiu, Upper Peru. 
3. CHATOSTOMUS MARCAPATA, sp. n. (Plate XIV. fig. 1.) 
Depth of body about 5? times in the total length, length of head 5 times. Head as 
broad as long and 2} times as long as deep. Diameter of eye 6 times in the length of 
head, interorbital width 23 times, length of snout 1% times. Length of mandibular 
ramus 1} times in the interorbital width. Interoperculum with 11 or 12 spines. 
24 scutes in a longitudinal series, 8 between dorsal and adipose fin, 13 between anal 
and caudal. D. 17; the first ray } the length of head, the last 3 as long; length of 
