FISHES OF THE FAMILY LORICARIID®. 313 
Three examples from the Huamani Peak, Ecuador, 10,700 feet, received from the 
Paris Museum as Brontes prenadilla. 
8. ARGES ORIENTALIS. (Plate XXI. fig. 4.) 
Arges orientalis, Bouleng. Ann. Mag. Nat. Hist. (7) xi. 1903, p. 601. 
Length of head 33-4 times in the total length. Interocular width less than the 
distance from eye to posterior nostril, 53—4 times in the length of head. Outer series 
of teeth of the premaxillaries unicuspid; mandibulary teeth bicuspid ; barbel extending 
3-3 of the distance from its base to the gill-opening. First dorsal ray equal to 3—% 
the length of head; pectoral spine not extending beyond base of ventral; ventrals 
originating below the first dorsal ray, extending about 3 of the distance from their base 
to the anal opening, which is situated at 3-3 of the distance from the ventral to origin 
of anal. Adipose fin, if present, very feebly developed, without or with a rudimentary 
imbedded spine. Distance from the tip of snout to the base of first dorsal ray 2} times 
in the total length, from the base of last anal ray to the caudal 6-63 times. Olive or 
yellowish above, spotted or marbled with dark brown; caudal with dark spots. 
Total length 80 mm. 
Ten specimens from the Albireggas and Milla Rivers, above Merida, Venezuela. 
9. ARGES BRACHYCEPHALUS. (Plate XXI. fig. 8.) 
Arges brachycephalus Giinth. Proc. Zool. Soc. 1859, p. 92, and Cat. Fish. v. p. 222 (1864). 
Length of head 4-4} times in the total length. Interocular width equal to or a 
little less than the distance from eye to posterior nostril, 54-34 times in the length of 
head. Outer series of teeth of the preemaxillaries unicuspid; mandibulary teeth 
bicuspid; barbel extending to beyond the gill-opening in the young, }~— of the distance 
from its base to the gill-opening in the adult. First dorsal ray equal to ?-{ the length 
of head ; pectoral spine extending to anterior 3 of ventral; ventrals originating below 
the first dorsal ray, extending to the anal opening, which is situated at 3 of the distance 
from base of ventral to origin of anal; adipose fin long and low, not well developed, 
without trace of a spine. Distance from tip of snout to base of first dorsal ray 2% 
(young) to 24 (adult) times in the total length, from base of last anal ray to the caudal 
4141 times. Brownish, spotted or marbled with darker; some dark spots on the 
basal parts of the dorsal and caudal. 
Total length 218 mm. 
Ten specimens, including the types of the species from the Andes of Peru, and others 
from Cuenca, Ecuador. 
10. Arges cHoT#, sp.n. (Plate XXI. fig. 5.) 
Length of head 43 times in the total length. Interocular width a little greater than 
the distance from eye to posterior nostril, 33 times in the length of head. Outer 
272 
