342 PROCEEDINGS OF THE ACADEMY OF [DeC, 



though stronger than in Spirinchus, the scales smaller, the gill- 

 rakers longer and the lower jaw heavier. Eperlanus is an old name 

 of the European smelt, Osmerus eperlanus L. It has been already 

 used as a synonym of Osmerus. Eperlanio is an unused variant. 



ERYTHROCLES Jordan. 



Type: Erythrichthys schlegeli Bleeker, the name a substitute for 

 Erythrichthys Temminck & Schlegel, preoccupied by Erythrichthys 

 Bonaparte (Saggio, 1831), based on Salmo erythrinus L. and there- 

 fore a synonym of Erythrinus (Gronow) Scopoli. Erythrocles is 

 one of several very closely related genera, Emmelichthys Richard- 

 son, Boxaodon Guichenot, Inermia Poey, Dipterygonotus Bleeker and 

 Plagiogeneion Forbes, but it seems to be distinct from all of these, 

 whatever their relation to one another. 



EXTRARIUS Jordan. 



Type: Hyhopsis tetranemus Gilbert. 



This genus is distinguished by the presence on each side of two 

 maxillary barbels as in the old-world genus Barhus. In other re- 

 gards it agrees with Macrhybopsis Cockerell {Gobio gelidus Girard). 

 No other known species of American minnow or chub has more 

 than two barbels. 



IRILLION Jordan. 



Type: Coregonus oregonius Jordan and Snyder. 



This genus differs from the other offshoots of Coregonus in the 

 long sharp nose, firm jaws, and in the very large adipose fin. It 

 frequents mountain streams and is as gamy as a trout. The name 

 is from "the merry wild Irillion rejoicing from fields of snow" of 

 Dunsany's dream world. 



NAUTOP^ffiDIUM Jordan. 



Type : Porichthys plectrodon Jordan & Gilbert = Batrachus porosis- 

 simus Cuv. & Val. 



This genus is closely allied to Porichthys Girard (notaius), differing 

 mainly in the palatine dentition. There are but four or five teeth on 

 each palatine, one or two of them developed as a strong canine. 

 In Porichthys there are many small palatine teeth, none of them ca- 

 nine-like. The name, Nautopcedium {'^ao-oTzacdur^, sailor-boy), refers to 

 the button-like luminous spots, which have suggested the vernacular 

 name of "Midshipman". 



OSHIMIA Jordan. 



Type: Micracanthus marchei Sauvage. 



Name a substitute for Micracanthus Sauvage, 1878, preoccupied 



