SOUTH AMERICAN NEMATOGNATHI. 163 



? Pimelodus Swainson, Fish. Amph. & Kept, ii, 305, 

 1837 ( quadrimaculatus ) . 



Pimelodus Liitken,Velhas Flodens Fiske, 43, Videiisk. 

 Selsk. Skr. xii. 2, 163, 1875 (maculatus = clarias). 



Pseudariodes Bleeker, Nederl. Tijdschr. Dierkunde, i, 

 1863, $9 (clarias). 



Pseudorhamdia Bleeker, 1. c. 101 ( maculatus clarias). 



Pseudorhamdia Liitken, 1. c. 49, 169, 1875 (fur). 



Type Pimelodus maculatus Lacepede. 



Bleeker, assuming that the first species mentioned by 

 Lacepede under Pimelodus was the type of Pimelodus, re- 

 stricted the genus Pimelodus to the Silurus bagre Bloch. 

 There is, however, no evidence that the first species men- 

 tioned by Lacepede was his type of Pimelodus, and as Cu- 

 vier restricted the name to those " qui out des dents en 

 velours aux deux machoires, mais ou lasuperieure n'eii a 

 qu'une band intermaxillaire," the type of the genus 

 must be selected from among them. In. 1839 Swainson 

 restricted the genus to quadrimaculatus, one of the 

 species enumerated by Cuvier, and also included in the 

 Pimelodus of Lacepede. 



The genus Pimelodus must therefore have for its type 

 Silurus quadrimaculatus Bloch, whatever that may be. 



In 1861 Gill restricted the name Pimelodus with macu - 

 'latus as its type. 



Liitken also proposes 'maculatus as the type. He also 

 restricted the name Pseudorhamdia Bleeker to fur, a spe- 

 cies entirely unknown to Bleeker. Still more inexcusa- 

 ble is the restriction of Steindachner of the same name 

 to still another species not belonging to this genus. 



If we disregard the many synonyms, the genus is 

 composed of well-defined species inhabiting the region 

 north of the Rio Plata and east of the Andes. 



.Teeth on the vomer in small patches or none; teeth 

 on the pterygoid in one species, otherwise the palate 



