GENERIC NAMES OF BUTTERFLIES 365 



was corax Fruhstorfer, [1919] (Pithecops hylax corax Fruhstorfer, [1919], Arch. Naturgesch. 

 83 Sect. A.i : 79). 



If the changes in nomenclature necessitated by Corbet's determination of the true identity 

 of Papilio hylax Fabricius had been put into effect, the results would have been disastrous, 

 leading to the most serious confusion both at the genus-name and at the species-name, levels. 

 These may be summarized as follows : 



(a) The species hitherto universally but incorrectly known by the specific name hylax 



Fabricius would in future have had to take the almost unknown name corax 

 Fruhstorfer, [1919]. 



(b) The species hitherto known by the well-known name gaiha Trimen, 1862, would in 



future have had to take the name hylax Fabricius, which had never previously been 

 applied to it. 



(c) The species hitherto incorrectly known as " hylax Fabricius'" with its name changed 



to corax Fruhstorfer would have been placed in the genus Eupsychellus Rober, 1891, 

 with the type-species of which [Lycaena dionisius Boisduval, 1832) it is subjectively 

 regarded as being congeneric. 



(d) The name Pithecops Horsfield with the true Papilio hylax Fabricius (a senior subjective 



synonym of Lycaena gaika Trimen) as its type-species would have replaced the 

 name Zizula Chapman, 1910, of which Lycaena gaiha is the type-species. 



(e) The genus Pithecops, as hitherto interpreted as having the false " hylax Fabricius " 



of Horsfield as type-species, is currently treated as belonging to the subfamily 

 Everinae Tutt, [1907] of the family Lycaenidae, while Zizula Chapman is considered 

 to belong to a different subfamily which Stempffer has named Brephidiinae (type- 

 genus : Brephidium Scudder, 1876). If the changes indicated in (c) and (d) above 

 were to be put into effect, the genus Pithecops would need to be transferred from 

 the subfamily Everinae to the subfamily ISrephidiinae. 

 While it was evident that a continuance of the practice of ignoring the position under the 

 Code of the generic name Pithecops Horsfield and of the species name Papilio hylax Fabricius 

 would be indefensible, it was evident also that it was essential in the interest of nomenclatorial 

 stability to seek the assistance of the Commission in securing a solution of the problem which 

 would prevent the devastating changes in existing nomenclatorial practice which would 

 result from the application in this case of the ordinary rules in the Code. What was chiefly 

 needed was an arrangement which would both (i) avoid the transfer of the specific name 

 hylax from the species to which it was applied by Horsfield nearly 140 years ago and has been 

 applied ever since to a species to which it had never been applied and (ii) would avoid a 

 corresponding change in the application of the generic name Pithecops Horsfield. It was 

 finally concluded that the best course would be to request the Commission to use its Plenary 

 Powers (a) to suppress for the purposes both of the Law of Priority and of the Law of 

 Homonymy the specific name hylax Fabricius, 1775, as published in the binomen Papilio 

 hylax, (b) to validate the name Pithecops hylax, as published by Horsfield in 1828, the taxon 

 so named to have as its holotype the specimen figured by Horsfield in 1828 as figure 2 on 

 plate 1 in the work referred to above, and (c) to designate the nominal species Pithecops hylax 

 Horsfield, [1828], as validated in (b) above, to be the type-species of the genus Pithecops 

 Horsfield, 1828. In accordance with the provisions of Article 80, the foregoing arrange- 

 ments are here adopted provisionally, pending a decision by the Commission on the applica- 

 tion submitted. 

 PLACIDULA Ferreira d'Almeida, 1922, Melanges lip. 1 : 67. Type-species by original 

 designation : Ithomia euryanassa Felder (C.) & Felder (R.), i860, Wien. ent. Monats. 

 4 : 101. 

 PLACILLA Moore, [August 1892], Lep. ind. 1 (n) : 253. Type-species by original desig- 

 nation : Lethe christophi Leech, 1891, Entomologist 24, Suppl. : 67. 



As explained in the note on the name Kirrodesa Moore, that name is currently treated as 

 a subjective synonym of Placilla Moore, over which it has some three month's priority. 



