PLEBEIUS ARGUS. 167 



and the fact that both argus ( = aegon) and argyrognomon ( — argus) 

 occur commonly in Scandinavia, we should be inclined to consider 

 argiis, Linn., either a combination of the two, then unseparated, species, 

 or that now known as argyrognomon, and, in this respect, should find 

 ourselves in agreement with Schiffermuller, Borkhausen, Ochsenheimer, 

 Zeller, and almost the whole race of European lepidopterists. Schiffer- 

 miiller (Sys. Verz., p. 183 note), and Borkhausen (Nat. Eur. Schmett., i. r 

 p. 294), whom most of the later authors* followed, had, as shown by 

 their writings, a full and clear knowledge of Linne's description of 

 argus (and idas); and decided it for argyrognomon, although Laspeyres. 

 (111. Mag., iv., p. 65) stated that further evidence was wanted. It 

 happens that, in our examination of the argus ( = aegon) in the British 

 Museum collection labelled "S. Norway," and "Odalen, Norway 

 (Salvin)," and a specimen in our own collection " Saeterstoen (Chap- 

 man)," we were struck by the fact that the $ s are of the bright "plain " 

 or "lowland" form (in contradistinction to the " heath," " moss," and 

 " mountain " forms), with a rather narrow marginal border to the fore- 

 wings, and with dots on the hindmargin of the hindwings, rather than 

 a dark border. This might account for the absence of any mention 

 of the marginal border, so conspicuous in some forms, in Linne's 

 description, and, added to the fact that, in the Linnean collection at 

 Burlington House, there are no argyrognomon at all, whilst there are 

 seven aegon (four, however, evidently added since its arrival in England, 

 and labelled, in Smith's handwriting, as English), one without any 

 label, and the other two without locality data, but labelled, in Linne's 

 handwriting, the $ "1074," the $ "1075 idas," the numbers correspond- 

 ing with those attached to argus and idas in the Fauna Suecica, 2nd 

 ed., p. 283, and which are possibly the original Linnean types of this 

 insect, suggests caution. This $ , however, has a rather broad margin. 

 Schoyen writes (Fnt. Tids., in., pp. 33-62 [resume in French, pp. 100-102] , 

 transl. Ent. Xach., viii., pp. 213, 214, 276) an interesting note on the 

 subject of the Linnean argus, stating that Wallengren had first (!) 

 referred argus, Linne, to aegon, Schiff., and that McLachlan had supported 

 this statement by adding that the " typical examples of P. argus in the 

 collection of Linne were identical with the aegon so common in Britain." 

 On such uncertain ground, therefore, and as the species hitherto known 

 as aegon, Schiff., is now generally recognised as argus, Linn., we follow 

 the more recently-expressed view of the matter. 



Original description.! — Argus. P. P. alis ecaudatis casruleis ; 

 posticis subtus limbo ferrugineo ocellis caeruleo-argenteis. [" Fn. 

 Suec," 803. 804. De Geer, "Ins.," t. 4, f. 14, 15. Wilk., " Pap.," 



* The early French authors (including Latreille), however, following Ernst 

 and Engr., Pup. d' Europe, pi. xxxviii., no. 80, largely applied the name to icarus, 

 see also Borkhausen, Nat. Eur. Schmett., i., pp. 275-6. 



f The two specimens in the Linnean collection at Burlington House, labelled 

 by Linne, may be described as follows : — " 1074. $ (argus) brightish purple-blue, 

 with rather broad suffused black band, spots of hindwing completely lost in the 

 band ; underside hindwing with very white band inside a bright orange lunular 

 band; silver spots not pronounced (underside forewing invisible)." "1075. ? 

 (idas) unicolorous brown on upperside, not very dark, but with faint indications of 

 orange lunules on hindwing ; underside with very white band inside the bright 

 orange lunular band ; silvery-blue spots well marked ; ground-colour coffee- 

 brown " (Wheeler. April 7th, 1909). . . 



