88 CALIFORNIA ACADEMY OF SCIENCES. 



Head 3J; depth 5; D. I, 6; A. 19. 



This species is known only from the type. One 

 specimen, No. 7,670; length .235 m. Rio Grand do 

 Sul. Senhor Albuquerque. 



59, Tachisurus fissus, 



Arius fissus Cuv. & Val. Hist. Nat. Poiss. xv, 107, 1840 (Cayenne); 



Giinther, Cat. Fish. Brit. Mus. vol. v, 172, 1864 (Cayenne); 



Bleeker, Silures de Suriname, 52, pi. iv, fig. 1, 1864 (Surinam). 

 Gakichthys jissus Jordan, Proc. U. S. Nat. Mus. 1886, 558 (name 



only). 

 Tachisurus Jissus Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. vol. i, 



1888, 146 (name only). 

 f Arius puncticulatus Cuv. & Val. Hist. Nat. Poiss. xv, 108, 1840 



(Buenos Ayres). 

 Habitat: Northern coast of South America. 



60, Tachisurus melanopus, 



Arius melanopus Gtinther, Cat. Fish. Brit. Mus. v. 172, 1864 (Kio 

 Motagua); id. Fish. Cent. Am. vi, 1866, 393 (name only); Stein- 

 dachner, SB. Ak. Wien, Ixxiv, 1876, Ichthy. Beitr. iv (Panama). 



Gakichthys melanopus Jordan, Proc. U. S. Nat. Mus. 1885, 366 

 (name only); Jordan, Proc. U. S. Nat. Mus. 1886, 558 (name 

 only). 



Tachisurus melanopus Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. 

 vol. i, 1888, 146 (name only). 



Habitat: West Coast tropical America. 



61, Tachisurus spixii 



Pimelodus albidus Spix, Gen. Spec. Pise. 19, pi. vii, fig. 1, 1829 

 (Equatorial Brazil). 



Pimelodus spixii Agassiz in Spix. Gen. Spec. Pise. 19, 1829. 



Arius spixii Cuv. & Val. Hist. Nat. Poiss. xv, 76, 1840 (copied). 



Tachisurus spixii Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. vol. 

 i, 1888, 146 (Maranhao; Bahia; Kio Janerio; Para; Santos in Sao 

 Paulo; Abrolhos). 



Arius arenatus Cuv. & Val. Hist. Nat. Poiss. xv, 106, 1840 (Cay- 

 enne); Giinther, Cat. Fish. Brit. Mus. vol. v, 172, 1864 (cop- 

 ied); Bleeker, Silures de Suriname 53, pi. iv, fig. 2, 1864 

 (Surinam). 



Gakichthys arenatus Jordan, Proc. U. S. Nat. Mus. 1886, 558 (name 

 only). 



Arius laticeps Giinther, Cat. Fish. Brit. Mus. v, 171, 1864 (Brit. 

 Guiana; Trinidad). 



Gakichthys laticeps Jordan, Proc. U. S. Nat. Mus. 1886, 559 (name 

 only). 



Habitat: Santos to Surinam. 



