330 CALIFORNIA ACADEMY OF SCIENCES. 



Back and sides marbled with light and dark brown; 

 lins pale, immaculate. 



Head 5^ (6i in the total); depth 7* ; D. 15; A. 9. 

 One specimen .092 m. Rio Mapocho, Chile. 



259. Pygidium areolatum. 



Trkhomycterus areolatus Cuv. & Val. Hist. Nat. Poiss. xviii, 492, 

 1846 (Coast of Chile); Gay, Hist. Chile, ii, 309, 1848; Giinther, 

 Cat. Fish. Brit. Mus. v, 274, 1864 (Chile); Philippi, MB. Ak. 

 Berlin, 714, 1866. 



Thrichomyctcriis maculatus Girard, U. S. Naval Astron. Exped. 243, 

 1855 (Mapocho), in part. 



Pygidium areolatum E. & E. Proc. Cal. Acad. Sci. 2d Ser. ii, 51, 

 1889 (Eio Mapocho, Chile). 



Habitat: Western slojie of Centi'al Chile. 



Elongate, subterete. Lips and lower surface of head 

 thickly covered with small warts. Gill-openings con- 

 tinued forward to below the eye, the membrane free from 

 the isthmus. Upper maxillary barbels reaching to the 

 pectorals. 



Pectorals rounded, the first ray not prolonged; origin 

 of dorsal slightly in front of the vent, equidistant from 

 tip of caudal and occiput, its last ray over the fourth 

 ray of the anal. Caudal very slightly emarginate. Dis- 

 tance of anal from the base of the caudal 5 in the length. 

 Origin of ventrals equidistant between tip of snout and 

 middle of caudal; tips of the ventrals not reaching the 

 vent. 



Light brown, with purple longitudinal streaks. 



Head 5f (6| in the total); depth 8^^; D. 14; A. 8. 



One specimen .103 m. Mapocho, Chile. 



260. Pygidium rivulatum. 



TrichoTnycterus rivulatus Cuv. & Val. Hist. Nat. Poiss. xviii, 495, 

 1846 (Guasacona); Giinther, Cat. Fish. Brit. Mus. v, 274, 1864 

 (copied); Cope, Proc. Am. Philos. Soc. xvii, 47, 1877 (Lake 

 Titicaca). 



Pygidium, rivulatum E. & E. Proc. Cal. Acad. Sci. 2d Ser. ii, 51, 

 1889 (Cuzco; Moho and Puno on Lake Titicaca.. 



.? Trichomycterus inae Ciiv. & Val. 1. c. 496 (Kio Guatanai at Cuzco). 



