INTRODUCTORY PAPERS ON LEPIDOPTERA. 149 



of this region, are always interesting and valuable. A great 

 number of peculiar forms are confined to the Indian region, 

 while others show more or less affinity with Europe, Africa, 

 or Australia. It is to be noted that Indian specimens of 

 insects common to India and Europe, or North Asia, are 

 generally considerably smaller in India, owing, perhaps, to 

 the more rapid development of the larvae in a hot climate. 

 Wallace subdivides this region into subregions as follows : — 

 1. Hindostan, or Indian subregion ; 2. Ceylon and South 

 Indian; o. Himalayan, or Indo-Chinese; 4. Indo-Malayan, 

 including the Malayan Peninsula ; Borneo, Java, and Suma- 

 tra. The divisions explain themselves ; and as their cor- 

 rectness is much disputed, we will not further notice them. 



IV. Australian Region. — Includes Celebes, New Guinea, 

 Australia, and New Zealand, the Polynesian Archipelago, 

 and all the islands between or near those already mentioned. 

 The aflfinilies of this region are chiefly with the last, though 

 many of the cliaracteristic Indian forms are wanting. On 

 the whole, the fauna is poor, though some groups (for 

 example, Papilio) attain their maximum of size and beauty 

 here. Australia itself is more remarkable for peculiar forms 

 of Lepidoptera-Helerocera than for its butterflies. Wallace 

 divides the Australian region into lour subregions as 

 follows: — 1. Austro-Malayan Subregion {Papua, Moluccas, 

 &c.) ; '2. Australian ; 3. Polynesian ; 4. New Zealand. 

 Butler's ' Catalogue of Lepidoptera of New Zealand,' form- 

 ing part of the ' Zoology of the Voyage of the Erebus and 

 Terror,' is the only general work on the Lepidoptera of any 

 part of the Australian region. Except from South Australia, 

 specimens are only obtainable casually from this part of the 

 world, when the islands of which it consists happen to have 

 been recently visited by collectors. 



V. Neotropical Region. — Comprises South and Central 

 America, the West Indies, and a great part of Mexico. 

 This region is probably by far the richest in Lepidoptera of 

 any in the world ; it produces more than half the known 

 butterflies, and whole families are almost if not entirely 

 confined to it. It is said that over '2000 species of butterflies 

 are met with in the valley of the Amazon alone. Wallace 

 divides it into subregions as follows: — I. Tropical South 

 American or Brazilian Subregion ; 2. South Temperate, 



