INFLUENCE OF RAINFALL ON DISTRIBUTION OF SPECIES. 501 



in a tree from 100 to 150 yards off, and again commence their 

 cackling-. 



u When feeding, they are found as low as from 30 to 40 feet 

 from the ground, but when disturbed, they fly straight off 

 to the tops of the highest trees about. They never, when 

 feeding, sit for more than, at the most, a minute in one place, 

 but are constantly bustling, flying, and sailing about. The 

 parties I saw consisted of from eight to eighteen birds, though 

 generally from eight to ten. The chief food seems to be berries, 

 but I twice found remains of some kind of fly in their 

 stomachs." 



A. O. H. 



[nfltteu.cc d UainMl on Distribution of Species. 



On a recent occasion (vide ante, p. 53), I pointed out how 

 great an influence the total annual average rainfall had on the 

 distribution of birds. 



I said : — " It is customary to talk of the Malayau facies, of 

 the Fauna of the Malabar Coast, the Assamboo Hills and part 

 of Ceylon ; what is this but that in these localities j'ou recover 

 the heavy rainfall of the Malay Peninsular ? How the same 

 species or representative forms found their way to these distant 

 localities is another question, but their survival in each is due 

 primarily to the extent of the rainfall. 



" What gives such a plains of India facies to the dry upper 

 portions of Pegu, but the light average rainfall ? What 

 allows the Indo-Malayan species to run up westward along the 

 feet of the Himalayas, at any rate as far as the Ganges, but the 

 heavy rainfall ?" 



When this was written no chart had been published so far as 

 I know illustrating these views. 



Later, however, a small map of India, approximately showino- 

 the mean annual rainfall of the various provinces, was prepared 

 for other purposes, and I am able to present my readers with 

 a copy of this. 



A glance at this affords one important key to the entire 

 distribution of species in India. 



We see at once why the West Coast, Tenasserim, Lower Pegu, 

 Arakan, Eastern Bengal, Assam, and the Sub-Himalayan tracts, 

 have such veiy similar avifaunas ; why the birds of the 

 Dekhan and parts of the North- West Provinces and the Punjaub, 

 Rajpootaua and Kattiawar are almost identical ; why so 



