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XII. Some hionomir notes on Butterfiics from the Victoria 

 Nyanza. By S. A. Neave, M.A., B.Sc, F.E.8., 

 Magdalen College, Oxford. 



[Read June 6th, 1906.] 



Plates IX— XII. 



The following notes on the bionomics of African butterflies 

 mainly refer to the large collection recently sent to the 

 Hope Department, Oxford University Museum, by Mr. C. 

 A. Wiggins, M.R.C.S., F.E.S., etc., etc. This magnificent 

 collection, with excellent data, has already been described 

 in Nov. Zool. vol. xi, pp. 323-363, 1904. 



A further large and important collection from the same 

 region, made by Mr. A. H. Harrison, has also been made 

 use of to some extent. Where numbers are given, they 

 generally refer to Mr. W^iggins' collection only. 



The district whence these specimens come proves itself 

 to be of peculiar interest to students of geographical dis- 

 tribution. It is here that we have a great commingling 

 of Eastern and Western forms. In the list of specimens 

 in the paper above referred to will be found records of 

 such species as Ehjmnias inhegea, Fabr., Bicyclus iccius, Hew., 

 many species of Planema, Euxanthc crossleyi, Charaxes 

 zingha, Cram., to mention only a few, all of which until a 

 few years ago were thought to be species confined to the 

 tropical West Coast of Africa. These are mingled among 

 many truly East African forms. 



As will be seen \aitQY,A.niaviu)^ and dominieanus, or'igxndiWy 

 described as distinct species and subsequently considered 

 distinct forms, are now shown to form a syngamic group. 

 This extension of the Western fauna to E. Central 

 Africa is most probably due to the extension eastward of 

 dense forest land, similar to that on or near the western 

 tropical coast. The climate on or near the equator has 

 apparently much less defined wet and dry seasons, resulting 

 in a humid atmosphere and equable temperature more 

 suitable to the growth of dense vegetation. 



This absence of well-defined w^et and dry Feasons has a 

 marked effect on the seasonal forms in the Lepidoptera of 

 the country, well-marked seasonal characters being relatively 

 scarce. In studying the mimetic groups in such a large 



TRANS. ENT. SOC. LOND, 1906, — PART II. (SEPT.) 



