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XII. Some bionomic notes on Butterflies from the Victoria 
Nyanza. By S. A. Nave, M.A., B.Sc, F.ES., 
Magdalen College, Oxford. 
[Read June 6th, 1906.] 
Puatres 1X—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., ete. etc. This magnificent 
collection, with excellent data, has already been described 
in Nov. Zool. vol. x1, pp. 325-363, 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. Wiggins’ 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 Hlymnias phegea, Fabr., Bicyclus iccius, Hew., 
many species of Planema, Huxanthe 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 Kast African forms. 
As willbe seen later, A. niavius and dominicanus, originally 
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 wet and dry seasons 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.) 
