548 Appendix to R^FK. St. Aubyn Rogers' Bioiumiic 



$ ; black spots as in $. Forewing : fuscous area duller and 

 with a brownish tinge. Hind-ioiwj : a very broad brownish- 

 fuscous hind-marginal border, very diffused on its inner 

 side. Under side. — Very much duller and paler than in 

 $ throughout, and but little differing from that of typical 

 form $, except that median inner-marginal space in fore- 

 Aving is of a decidedly paler tint, in accordance with 

 "whitish area on upper side. 



It is not improbable that the single $ of ruhesccTis here 

 described is not the normal form of that sex, but a second 

 form of the kind not unfrequent in the genus, where white 

 or whitish more or less suffuses or takes the place of the 

 ordinary red or fulvous ground colour, usually in the hind- 

 wing only.* The normal $ will probably be found to 

 resemble the ^ asbuloplintha (which is of much duller and 

 fainter colouring than the $), except as regards on the 

 upper side a more rufous hind-wing, and a rufous median 

 space in the fore-wing. 



The $ rubesecns obviously stands in much the same 

 relation to $ asholojjlmtha as A. acara, He wits., does to 

 A. zetes, Linn., A. cepheus, Linn., to A. eginopsis, Auriv., 

 A. natalica, Boisd., to A. psendegina, Westw., and A. areca, 

 Mab., to A. egi7ia, Cram., vid.: that of generally brighter 

 colouring and especially of rufous ground colour in the 

 fore-wing instead of fuscous. This relation is associated 

 with a different geographical range in the cases mentioned, 

 the brighter forms being in three instances East and South- 

 East, and the obscurer West African, linking gradations 

 occurring in the intermediate areas; but ruhescens and 

 asboloplintha are found side by side in British East Africa, 

 as are also areca and egina in Nyassaland.f 



The isolated iDosition, as sole representative of a sub- 

 group of his second group of the genus Acrxa, assigned to 

 A. asholopl'mtha by Aurivillius,| does not seem to me to 

 be a natural one, its respective neighbours assigned on 

 either side being A. satis, Ward, the last species in sub- 



* In a striking variety (A. pseiidulijciit, Butl.) from Congo and 

 Angola of ^4 . acara, Boisd., the entire Held of Ijoth wings — except an 

 ill-defined yellow-ochreous band just before liind-niarginul black 

 border of fore-wing, is pure wliite in Ijotli sexes. A. albo-radiata, 

 Auriv., the very close Zandjesian ally of ^. anemoaa, Hewits., also 

 presents in both sexes some broad pure-white sub-apical rays in the 

 fore-wing, and a large pure-wfiite discal space in the hind-wing, 



t Aurivilliup, " Rhop. /Ethiop.," pp. 508-10(1899). 



I Op. cit., p. 90. 



