NO. 1503. AMAZON FISHES— EIOENMANN AND BEAN. 665 



Steindachner has" called attention to this prolongation of the tin 

 rays in the males. 



The g-enus Cetopsls, as understood In' P^igenmann and Eigenniann, 

 contains four distinct generic types; one of these was described by 

 Agassiz (Cetopsis); two others by. Bleeker {Ilemicetopst'.s and Ps^u/do- 

 cetopsis); the fourth, with occldentaJis as the type, may t)e named 

 Paracetopsts (see tig. 3). 



The genera may be diagnosed as foIloAvs: 



a. Teeth conical or incisor-like; those on the vomer in a single series. Ventrals free 



or united to the belly Hemiceio}»<ls 



aa. Teeth on premaxillary villiform, in a band; those on the vomer and on the 

 mandible incisor-like in a single series. Ventrals partly united to the 



belly Cefopsis 



aaa. Teeth on the premaxillary and mandible villiform, in l)ands; those of the 

 vomer in one or more uninterrupted series, incisor-like; ventrals united 



with each other Pseudocelopsis 



aaaa. Teeth all villiform, in l)ands, those on vomer in twj patches; ventrals 

 partly joined to the Ijelly Paracetopsis 



LORICARIA CATAPHRACTA Linnaeus. 



Nine specimens. 



PLECOSTOMUS PLECOSTOMUS (Linnaeus). 



Four specimens. 



PSEUDACANTHICUS SPINOSUS (Castelnau). 



One specimen. 



HEMIANCISTRUS VITTATUS Steindachner. 



Two specimens. 



PTERYGOPLICHTHYS MULTIRADIATUS (Hancock). 



Three specimens. 



ANCISTRUS DOLICHOPTERUS Kner. 



Two specimens. 



HOPLOSTERNUM THORACATUM (Cuvier and Valenciennes). 



One specimen. 



STERNARCHELLA SCHOTTI (Steindachner). 



One specimen 7^ inches long. 



«Flussf. Sudani., IV, p. 5. 



