412 EXPLORATIONS ACEOSS THE GEE AT BASIN OF UTAH, 



first part of liis " Museum Ichthyologicum", where two species of the geniis Bhnnidia 

 of Bleeker were referred to it. The name of 3Iystus woukl have to be then retained 

 for that genus had it not been previously appKed by Klein to a genus of Cyp™oids. 



The Cuvierian section of Machoirans included all those Siluroids wliich had two 

 dorsal fins, the fii'st of which was rayed and the second adipose. There were conse- 

 quently referred to it the Pimelodi, Ageneosi, and Doradcs of Lacepede. The Ma- 

 choir cms were again divided into groups, for which were retained the above names of 

 Lacepede. 



Finally, Pinielodus of Lacepede was itself taken with the limits assigned to it by 

 its founder, and divided into tlu-ee subgenera characterized by their dentition. 



The first of these was Synodontis of Cuvier, which included the third species of 

 tlie Lacep^dian genus Pimehdus — Le Pmelode scheikm. 



For the second subgenus, the Laci^pedian name of Pimehdus was retained. It 

 was intended to include those which had teeth only on the intermaxillaries and den- 

 taries. 



The third subgenus was named Bagrus, and included those which, in addition to 

 the teeth on the jaws, had a parallel band on the vomer. 



To that genus were referred the first,* fourth,t thirteenth,t seventeenth, § and 

 eighteeuth|| species of Lacdpfede's genus Pimelodus. The ninth species of Lacepfede** 

 was considered as synonymous with his thirteenth. To illustrate the sequence and 

 relative vahie assigned by Cuvier to his various groups, we subjoin the following 

 extract from his methodical index : 



Machoirans (Mystus Artedi). 

 PiMELODEs Lacep. 

 Shals {Synodontis Cu.v.). 



PiMELODES PEOPEEMENT DITS (Pimelodus Cuv.). 



Bagres. 



Ageneioses Lacep. 

 DoEAS Lacep. 



The next naturalist who circumscribed the geniis was Rafinesque. That writer, 

 in the " Iclithy ologia Oliiensis", retained Pimelodus as the name of a genus, and the 

 characters assigned by him to it were not essentially different from those of Lacdpede; 

 he added that the adipose fin is separated from the caudal. By that feature, he distin- 

 guished the genus from his Noturi, in which there is an "adipose fin very long, decur- 

 rent, and united with the tail". 



The species of the Ohio referred to the genus so limited were placed in a subgenus 

 called Ictalurus, which exactly corresponds to Pinielodus as restricted by Dr. Girard in 

 the Report on the Ichthyology of the Pacific Raih-oad Sm'veys. The diagnosis of Icta- 



* Pimelodus bagrus Lac. = Aihtrichthys iagrus GUI/ 



t Pinulodiis fasciatiis Lac, = 5ocKJii«Hi fasdatum Gill. 



t Pimelodus commersonii I^iic. = Giiirilinga conimersoiiii IJlcekor. 



^ Pimelodus docmac Lac. = Bagrus docmac Cuv. 



II Pimelodus bayad lja,c. = Hagrus bayad Cuv. 



** Pimelodus barbus Lac. — 



