1893.] ME. E. T. WATSON OIT THE HESPEEIID.!:. 5 



importance to Scudder's Hesperidi and PamphiUdi, this latter being 

 an alteration already suggested by Scudder himself. 



Passing by the arrangement of Plotz, which, being based largely 

 on the pattern of the wings, has been found quite unworkable, and 

 that of Distant, which was a tentative one only intended to be applied 

 to the fauna then under consideration, we come to a valuable paper ' 

 by Speyer on the " Genera of the Hesperiidae of the European 

 Fauna." In this paper he makes a suggestion which has been found 

 of the very greatest importance in the classification of the genera ; 

 this suggestion was to the effect that the position of vein 5 of the 

 fore wing in relation with veins 6 and 4 would probably prove a 

 character of value. This surmise has proved to be correct, and the 

 position of vein ;i has been found of great use in the arrangement of 

 the Hesperiidse, as it has already proved to be for the division of 

 the Heterocera into two large groups of families. 



In the following arrangement it has been attempted to make 

 mention of every generic name published prior to lb92, and to point 

 out its type species, though, where this species has not been acces- 

 sible, it has not been jjossiblc in most cases to assign the genus to 

 its correct position. This is in great part owing to the very super- 

 ficial manner in which some, even recent, authors characterize their 

 genera, in manv cases doing no more than sjiecifying the species 

 they propose as their type, so that when one is not in possession of 

 that particular species the genus is quite unrecognizable. 



Whenever no particular species has been designated by the author 

 of a genus as his type of tliat genus, it has been found most satis- 

 factory to follow Scudder's ' Historical Sketch of the Genera of 

 Butterflies,' published in 18/5, as in that work he has investigated 

 the history of the genera from the earliest authors, and has fixed 

 the types in accordance with the strictest rules of priority, and there- 

 fore in the opinion of the writer his decisions should be accepted by 

 all subsequent authors, who will thus have a sound basis to start 

 from, and a uniform system would result instead of the chaos which 

 is caused by eacli author arbitrarily fixing the type of the genera of 

 earlier authors on a system of his own. 



The decisions of Mr. Scudder have therefore been accepted for 

 all genera included in the above-quoted work ; while for those 

 genera which have been described subsequently, when no type has 

 been specified, that species has been taken which best agrees with the 

 diagnosis of the genus. In the great majority of genera it has been 

 found practicable to clear the wings of a specimen of the typical 

 species, whereby its diagnosis has been considerably facihtated. 



In all, 234 generic names have been dealt with, of which 49 are 

 sunk as synonyms, while 4.5 new genera have been described, and 

 at least as many more await description in British collections 



alone. 



As in the British ^Museum collection the two genera Megathym- 

 nus and ^yiale are arranged in the Heterocera, they are not in- 

 cluded below, though some authors consider they should be treated 



1 Stett. ent. Zeit. vol. xl. p. 477 ef seq. (1879). 



