39 8 PATAGONIAN EXPEDITIONS: ZOOLOGY. 



Family HYPOPHTHALMID^. 



HELOGENES Gunther.' 

 Type: Helo genes marmoratus Gunther. 

 Range that of the single species. 

 i. Helo genes marmoratus Gunther, 



E. & E., 313- 

 Habitat: Essequibo. 



HYPOPHTHALMUS Spix. 

 Type : Hypophthalmus edentatus Spix. 



Family PYGIDIID^E. 

 Subfamily CETOPSIN.E. 



Notophthalmus Hyrtl ; Pseudohypoph- 

 thalmus Bleeker. 



Hypophthalmus edentates Spix, 



E & E ^ 3I3 



Hypophthalmus marginatus, longifilis 

 and s p ixii Cuvier & Valenciennes; 

 H edentulus Castelnau; H. fimbri- 

 atus Kner ; H. perporosus Cope. 



Habitat : Amazons and tributaries, and 

 northward. 



HEMICETOPSIS Agassiz. 



Type : Silurus candiru Spix. 



Range: A narrow area from Para to 

 , 



Al. Hemicetopsis candiru (Spix), 



E. & E., 319. 

 . _ 

 Habitat: Rio Cupai to Rio Huallaga. 



A2. Hemicetopsis plumbeus Steindachner, 





 E & E 320. 



Habitat: Canelos. 



CETOPSIS Agassiz. 



Type : Silurus ccecutiens Lichtenstein. 

 Range that of the single species. 

 Ai. Cetopsis ccecutiens (Lichtenstein), 



E. & E., 320. 



Habitat: Amazon from Gurupa to Rio 

 Cupai; Orinoco; Irisanga. 



Subfamily 

 NEMATOGENYS Girard. 



Type : Trichomycterus inermis Guiche- 

 not 



Range that of the single species. 

 Nematogenys inermis ( Guichenot) , 



E. & E., 323. 



Nematogenys nigricans and pallidus 

 Philippi. 



1 This genus is a member of a new family. 



PSEUDOCETOPSIS Bleeker. 

 : Cet P sis Sobioides Kner. 



: Irisan S a > Maranon. 

 I. Pseudocetopsis gobioides (Kner), 



Habitat: Irisanga. 



A2. Pseudocetopsis ventralis (Gill), 



v ' 



Habitat: Maranon. 



A3. Pseudocetopsis macroteronema (Boul- 



. D , T o^ Q 



enger), ........ Boulenger, 1898, 8. 



Habitat: Rio Zamora, eastern Ecuador. 



CETOPSOGITON Eigenmann & Bean. 



Type : Cetopsis occidentalis Steindach- 



ner. 



i. Cetopsogiton occidentalis (Steindach- 

 ner), .............. E. & E., 322. 



Habitat: Guayaquil. 



Habitat : Central Chili. 



PARIOLIUS Cope. 



Type : Pariolius armillatus Cope. 

 Range that of the single species. 

 A i. Pariolius armillatus Cope, 



E. & E., 324. 

 Habitat: Ambyiacu. 



