GENERIC NAMES OF BUTTERFLIES 281 



Westwood introduced what he called " Megastes Boisduval " in the synonymy of the name 

 Dynastor Doubleday, [1849]. Westwood did not state that his was a manuscript name but in 

 point of fact it was, not having been published by Boisduval until 1870. As a name published 

 in a synonymy, the name Megastes Westwood is invalid under Article 1 1 (d) which provides that 

 a name so published does not thereby acquire the status of availablity. Even if this name were 

 not invalid on the above account, it would by the type-selection made by Scudder in 1875, 

 have been invalid as a junior objective synonym of Dynastor Doubleday, [1849]. 



MEGASTES Boisduval, 1870, Consid. Lipid. Guatemala : 53. Type-species by selection by 

 Hemming (1943, Pyoc. R. ent. Soc. Lond. (B) 12 : 26) : Papilio darius Fabricius, 1775, Syst. 

 Ent. : 482. 



This is an available name, not being invalidated under the Law of Homonymy, the older 

 name Megastes Westwood, [1851], being a name published in a synonymy, possessing under 

 Article 11(d) no status in zoological nomenclature. 



MEGATHYMUS Scudder, 1872, 4th Ann. Rep. Peabody Acad. Sci. 1871 : 83. Type-species by 

 original designation : Eudamus (?) yuccae Boisduval & Leconte, [1834], Hist. gin. icon 

 Lipid. Chenilles Amir. sept. : pi. 70, figs (unnumbered) <$ [nee $], larva et pupa, [no text]. 



MEGISBA Moore, [1881], Lep. Ceylon 1 (2) : 71. Type-species by monotypy : Megisba 

 thwaitesi Moore, [1881], loc. cit. 1 (2) : 71, pi. 34, figs 3 rj, 3a $, 3b (larva et pupa). 



The taxon represented by the nominal species Megisba thwaitesi Moore is currently treated 

 subjectively on taxonomic grounds as being a subspecies of the taxon represented by the older- 

 established nominal species Lycaena malaya Horsfield, [1828] (Descr. Cat. lep. Ins. Mas. East 

 India Coy (1) : 70). 



MEGISTANIS Doubleday, 1844, List Spec. lep. Ins. Brit. Mus. 1 : 109. Type-species by 



selection by Hemming (1939, Proc. R. ent. Soc. Lond. (B) 8 : 134) : Papilio cadmus Cramer, 

 [1775], Uitl. Kapellen 1 (2) : 33, pi. 22, figs A, B. 



The taxon represented by the nominal species Papilio cadmus Cramer is currently treated 

 subjectively on taxonomic grounds as the same as that represented by the older-established 

 nominal species Papilio acheronta Fabricius, 1775 (Syst. Ent. : 501). There being no definite 

 information as to the exact dates in 1775 on which the Papilio cadmus Cramer and Papilio 

 acheronta Fabricius were published in 1775, the relative precedence to be accorded to these 

 names was a matter of doubt until in 1958 the Commission gave a Ruling under its Plenary 

 Powers in its Opinion 516 (Opin. int. Comm. zool. Nom. 19 : 1-44) as to the relative pre- 

 cedence to be accorded to names in various works published in 1775. Under that Ruling 

 the Commission gave directions, inter alia, that the Syst. Ent. of Fabricius of 1775 was to be 

 treated as having precedence before those portions of Cramer's Uitl. Kapellen published in the 

 same year. Thus, the specific name acheronta Fabricius, 1775, takes precedence above the 

 specific name cadmus Cramer, [1775], and on the basis of the subjective identification noted 

 above, becomes the oldest available name subjectively applicable to the present species. 



When establishing this genus, Doubleday, after citing cadmus Cramer, added as a second 

 species what he called " Megislanis beotus Boisd.? ". Scudder, overlooking the mark of 

 interrogation, selected this latter nominal species in 1875 (Proc. amer. acad. Arts Sci., Boston 

 10 : 213) to be the type-species. This action was invalid because when in 1844 Doubleday 

 established this genus, there did not exist any duly published nominal species bearing this 

 name. The species which in 1844 Doubleday had in mind was no doubt that which he himself 

 named Megistanis baeotus, (emendation of beotus) in [1849] (Gen. diurn. Lep. (2) : pi. 48, fig. 2). 

 Following Scudder's erroneous type-selection, this species was long known by the name Megi- 

 stanis, but that practice was seen to be quite unacceptable as soon as it was realized that the 

 true type-species of that genus was Papilio cadmus Cramer, these species not being considered 

 to be congeneric by the author during the last hundred years. The correction of the type-species 

 of Megistanis Doubleday left the species Megistanis baeotus Doubleday without an available 

 generic name. To make good this deficiency I introduced in 1939 the name Baeotus which 

 thus takes the place of the incorrect usage of Megistanis (i.e. Megistanis auct. nee Doubleday). 



