DISTRIBUTION OF PAPILIONID^ IN THE HIMALAYAS. 197 



either side, can, individually, rarely produce more than from one 

 to two dozen species — that is, from twenty-five to fifty per cent. 

 less than is the case in the small Sikkim section of the South- 

 eastern Himalayas. Even in the comparatively well-known and 

 much more extensive continental district of the Malay Peninsula 

 the number of species belonging to this particular family, as 

 recorded by Mr. W. L. Distant in his excellent work on the 

 * Butterflies of the Malay Peninsula,' falls short of the number 

 inhabiting the very circumscribed area of Sikkim by fourteen. 

 And what makes this fact the more remarkable still is that the 

 latter district is situated not only remote from the Equator, but 

 is wholly outside the Tropics besides. This singular superfluity 

 of species, however, is shared by all the other families and sub- 

 families of Ehopalocera, with the exception of the smaller 

 statistically and more strictly equatorial Euplseinse, Elymniinae, 

 Morphinas, and Nemeobiinse. In short, as the late lamented 

 Mr. Lionel de Nic6ville remarked to me upon the occasion of a 

 visit which I paid to him at the Indian Museum in Calcutta, 

 " Nowhere else in the Eastern Hemisphere will one find butter- 

 flies so abundant either in species or individuals." 



In some measure this is to be accounted for by the continuous 

 succession of phytogeographical and climatal conditions pro- 

 duced by the temperature and precipitation at different levels, at 

 least as regards the number of species is concerned, and pro- 

 vides a somewhat parallel case to the conditions which exist 

 in the Alps of Central Europe, the species becoming similarly 

 less numerous as one recedes therefrom upon either side. But 

 as regards the overwhelming number of individuals of many 

 species to be met with in the South-eastern Himalayas another 

 set of factors apparently comes into play. Without, however, 

 entering here into a discussion as to the cause or contributory 

 cause of the latter remarkable phenomena, I will just venture 

 the remark that in my opinion the organic competition in the 

 shape of animal enemies, chiefly ants, is possibly less severe in 

 the Himalayas than it is further south, an assertion founded 

 principally on personal observations in Ceylon, where, notwith- 

 standing the wonderful richness and marvellous luxuriance of 

 the vegetation, butterflies are comparatively very scarce in indi- 

 viduals (with a few exceptions), while ants, which probably 

 constitute their principal enemies in the adolescent state, are, 

 on the other hand, exceedingly abundant there. In this " Isle of 

 Spices," in fact, I found butterflies less plentiful in individuals, 

 and the number of species to be procured in a single day 

 frequently fewer than in many localities in the South of Eng- 

 land. That this was not my experience alone, I may recall the 

 fact that the late Sir Greville Smyth, whom I met collecting up 

 at Kandy upon various occasions, remarked to me that, although 

 he had made several visits to Ceylon, he had always found 



