( xxix ) 



with these papers Mr. Meyrick exhibited specimens of Oxy- 

 chirota paradoxa, Meyr. (unique specimens representing the 

 family Oxychirotidae), Epharpastis dadala, Meyr., and Mixo- 

 phyla erminea, Moore, and noticed two points bearing on 

 geographical distribution as follows : — 



"In connection with this and my previous papers on 

 Australian Pyralidina, two points bearing on the question 

 of geographical distribution suggest themselves. 



"(1). Many Pyrales — principally Botydida—h&ve a phe- 

 nomenally wide geographical range. It is a common thing 

 for the same species to occur unchanged in South Africa, 

 Mauritius, Ceylon, South Asia, the Malay Archipelago, 

 Australia, and through the South Pacific Islands to Tahiti ; 

 sometimes even extending into Central America. These 

 insects are usually of inconsiderable size and weak flight ; 

 they do not appear in great numbers, or show any special 

 migratory instincts. Yet immigration into Australia has 

 taken place on so large a scale that, out of 129 species of 

 Botydida established as occurring in Australia, 73 are found 

 to be more or less widely distributed outside the Australian 

 region. Most of these species are so far dependent on climate 

 that they do not range far outside the tropical line ; but, 

 apart from this, they seem to have little regard for barriers, 

 and little preference for one country as against another. It 

 must be a necessary condition of such wide distribution that 

 the larvae should either feed on plants of extraordinarily wide 

 range or be able to accommodate themselves to a variety of 

 food. Evidence as to this is as yet scanty, but certainly a 

 few do feed on common introduced weeds. I do not say that 

 these facts prove anything, but they seem to suggest that, 

 given a certain suitable climatic adaptability and a proper 

 provision in the way of food, sea-barriers, unless very wide or 

 very stormy, present no effectual obstacle to an insect endowed 

 even with the feeblest powers of flight. 



"(2). The distribution of this and other groups of Lepi- 

 doptera within Australia does not seem in any way to support 

 the theory advanced by Dr. Wallace as to the origination of 

 the peculiar Australian fauna within West Australia when 

 separated as a distinct continent from East Australia. The 



