250 ME. C. TATE BEGAN OX THE 



11. fClLETOSTOMUS BRA*y T ICKir. 



Vhatostomus branickii Steincl. Denkschr. Ak. Wien, xliii. 1881, p. 118, pi. vi. fig. 1. 



Length of head 3 times in the total length. Head as broad as long and about 

 If times as long as deep. Diameter of eye 8-9-^ times in the length of head, inter- 

 orbital width 3 times, length of snout 1^ times. Interoperculum with 6-10 spines. 

 23 scutes in a longitudinal series, 5 between dorsal and adipose fin, 9-10 between anal 

 and caudal. D. I 8, the first ray equal to ■§— f the length of head, the last ^ as long ; 

 length of base of dorsal little less than its distance from the caudal. A. I 4. Pectoral 

 spine extending a little beyond the base of ventral. Caudal slightly emarginate. 

 Yellowish brown, with little light spots on the head ; fins without spots, sometimes a 

 dark streak on each side of the dorsal rays ; tips of the caudal lobes light reddish. 



The typical examples, from Callacate, Peru, measure up to 135 mm. in total length. 



12. Ch^etostomus anomalus. (Plate XIII. fig. 2.) 

 Chcetostomus anomalus Regan, Ann. Mag. Nat. Hist. (7) xi. 1903, p. 599. 



Depth of body about 6 times in the total length, length of head about 3 times. 

 Head as broad as long and 2-2^ times as long as deep. Diameter of eye 8-12 times 

 in the length of head, interorbital width about 3 \ times, length of snout about If 

 times. Length of mandibular ramus a little greater than the interorbital width. 

 Interoperculum armed with 6-10 short spines. 24-26 scutes in a longitudinal series, 

 10-12 between anal and caudal. D. I 8 (rarely I 7 or I 9), the first ray equal to f— | 

 the length of head, the last f as long ; length of base of dorsal equal to |~f its distance 

 from the caudal. A. I 3-4 (exceptionally I 2). Adipose fin small, rudimentary or 

 absent. Pectoral spine scarcely reaching origin of ventral. Caudal peduncle 2-2^ 

 times as long as deep. Olive-brown, with rather large light spots on head and usually 

 on body; fins blackish, sometimes with rows of light spots or alternate light and dark 

 cross-bars, a black spot at the base of first interradial membrane of the dorsal. 



Total length 160 mm. 



Merida, Venezuela, and mountain-streams above it. 



Of 235 examples, 14 have a well-developed adipose fin, in 42 it is very small, in 78 

 more or less rudimentary, and in 101 wanting. In these last, however, a small, flat, 

 median plate represents the keeled scute which usually supports the spine of the 

 adipose fin. 15 examples have I 7 dorsal rays and 23 have 19. 2 have I 2 anal rays 

 and 47 have I 3. 



13. Celetostomus thomsoni, sp. n. (Plate XIV. fig. 2.) 



Depth of body 6f-7 times in the total length, length of head 3 times. Head as broad 

 as long and 2^ times as long as deep. Diameter of eye 7-9 times in the length of 

 head, interorbital width 3^-3f times, length of snout about If times. Length of 

 mandibular ramus equal to or a little greater than the interorbital width. Inter- 



