428 CALIFORNIA ACADEMY OF SCIENCES. 



ANALYSIS OF THE SPECIES OF PTERYGOPLICHTHYS. 



a. Interopercle small, with few or no spines. 



b. D. I, 10. undecimalis 398. 



66. D. I, 11; occipital roof-shaped; light brown, everywhere thickly 



covered with darker dots; membrane of adipose black. Head 2*-2f . 



etentaculatum 399. 

 666. D. I, 12-13, rarely I, 11 in pardalis. 



c. Occipital with a prominent ridge or knob; base of the dorsal at 

 least equal to its distance from the tip of the snout. Light or very 

 dark brown, everywhere with large and smaller spots of darker. 



gibbiceps 400. 

 cc. Occipital with a low median ridge or keel. 



d. Head and body spotted; dorsal fin as high as long; caudal fin 

 long, obliquely rounded, its lowest ray 2 in the length. 



punclatus 401. 

 dd. Head with narrow vermiculating lines, body spotted. 



e. Orbit 3-4J in the snout. pardalis 402. 



ee. Orbit 6| in the snout. (Cope.) jeanesianus 403. 



ddd. Uniform, ferruginous gray; D. I, 13. multiradiatus 404. 



aa. Interopercle large, freely movable, bearing a cluster of numerous 



setiform spines; dark brown with light spots and bars. 



lituratus 405. 



398. Pterygoplichthys undecimalis, 



Chcetostomus undecimalis Steindachner, Fisch-fauna des Magdaleneu 

 Str. 27, pi. viii, 1878 (Magdalen Rive~r); Steindachner, Fisch- 

 fauna des Cauca and Fliisse bei Guayaquil, 13, 1880 (Cauca). 



Pterygoplichthys undecimalis Eigenm. & Eigenm. Proc. Cal. Acad. 

 2d Ser. ii, 44, 1889. 



Habitat: Rio Magdaiena and tributaries. 



399, Pterygoplichthys etentaculatum. 



Hypostoma etentaculatum Spix, Gen. Spec. Pise. 7, plate iv, figs. 1 

 and 2, 1829 (Brazil). 



Pterygoplichthys etentaculatum Eigenm. & Eigenm. Proc. Cal. Acad. 

 2d Ser. ii, 44, 1889 (Bio San Francisco below the falls). 



Hypostomus duodeeimalis Cuv. & Val. Hist. Nat. Poiss. xv, 498, 

 plate 454, 1840 (Rio San Francisco; Saint Hilaire). 



Pterygoplichthys duodecimalis Giinther, v, 251, 1864 (Rio San Fran- 

 cisco). 



Hypostomus brevitentaculatus Ranzani, "Nov. Comm. Ac. Sc. Inst. 

 Bonon. 1842, 328." 



Ancistrus longimanus Kner, Hypostomiden, 283, 1853 (loc. ? ). 



Habitat: Rio San Francisco. 



There can be little doubt about the identity of etenta- 



