Notes on some British East African Butterflies. 553 



Acnea zetes, Linn.* I also pointed out, how variable 

 trimenii was in one important feature of its mimicry of 

 acara, vid. : the sub-apical yellow-ochreous bar of the fore- 

 wing, the gradation extending to its complete disappearance 

 in some individuals (P. colvillei, Butler), and so far ap- 

 proximating to P. hoisdiivalii, but at the same time exhibit- 

 ing no abatement in the distinctive feature of bright-red 

 instead of fuscous ground colour in the fore-wing. Later 

 on, in 1898, in the fine collection generously presented to 

 me by my friend Mr. Cecil N. Barker, I found 2 $ tri- 

 menii, having the yellow-ochreous bar of the fore-wing 

 only narrowly developed and mixed with white, but also 

 exhibiting a fuscous suffusion (considerably darker in one 

 example), so that the usual red of the fore-wing only 

 appears near the base. This fuscous clouding gives these 

 examples considerable resemblance to the $ hoisdnvalii, 

 but it must be noted that the reduced red of the fore- 

 wing is near the base, not near the posterior angle as in 

 hoisduvalii. 



I am now able, through the kindness of my friend Prof. 

 Poulton, to record the occurrence in a British East African 

 series in the Hope Department of 10 $ and 1 $ (see the 

 table on p. 527), of a ^ triincnii from " Rabai, near Mombasa 

 (K. St. A. Rogers) captured January 19th, 1907," in which 

 the sub-apical bar of fore-wing is very much reduced and 

 narrowed (while the red spots in the hind-marginal border 

 of hind-wing are unusually large), — having the fore-wing 

 fuscous suffusion largely developed, so that the usual red 

 ground colour is obliterated except for a large sub-quadrate 

 space at posterior angle as in P. hoisduvalii, and a slight 

 sub-basal trace. This example is a most distinctly inter- 

 mediate link between the Western and Eastern forms under 

 notice, and probably indicates another of the now rather 

 numerous cases in which presumed distinct species of 



* Haase (Untersucli. liber die Mimicry, etc., 1893, j). 43, taf. 4, 

 ff. 26-28) showed that boisduvalii mimicked A. egina, Cram., moi'e 

 closely than A. zetes, at any rate as far as the ^ is concerned, that sex 

 having a red patch along outer portion of inner margin of fore-wing, 

 just as in egiiui (J, and larger than is exhibited by zetes (J, while in 

 hind-wing larger black sj^ots characterise both egina and boisdHvalii. 

 On the other hand, as regards the presence of red spots in the hind- 

 marginal border of hind-wing, hoisduvalii resembles zetes and not 

 egina. It is noticeable also that in the feature last mentioned, the 

 mimicking West African Papilio ridleyanus, White, similarly 

 resembles zetes more than egina. 



