vi INDIAN PIGEONS AND DOVES 
way many other Natural History journals have references to Pigeons, 
but they also are scattered and difficult to find. Finally, so many 
of my friends and others have asked me to write a book on the Indian 
Pigeons, that I think there must be some grounds for hoping that 
a volume upon them will be kindly received. 
From a scientific point of view it is probable that this book will 
undergo considerable criticism, for it introduces for the first time 
into India the trinominal system—that is to say, the system which 
recognises subspecies. But India is essentially a country in which 
we find such a system necessary : for the variations in climate are so 
great, according to elevation, humidity, etc., that the same species 
in different localities are bound to undergo some degree of evolution 
which shall render them suitable to their surroundings. On the 
other hand, the variations so caused—though constant in definite areas 
—are often indeterminate in the country which links these areas 
together, and which is itself often intermediate in character. Then 
again we find in India parallel evolution going on in districts very far 
apart. For instance, the little Bustard-Quail (T'urnixz tatjoor) in the 
dry area of Southern Burma nearly approaches the same form as that 
found in the drier portions of Central India. So too, with our Pigeons : 
we find our very first bird, the Bengal Green Pigeon, having well- 
defined variations occurring both in Burma and in Southern India, 
yet in the intervening countries many birds cannot be placed with 
certainty under either form. 
It would appear, also, that Pigeons and Doves are birds very 
susceptible to climatic variations, for we known that Beebe, one of 
the leading American Ornithologists, has obtained different specific 
phases of plumage in the same identical individual by merely trans- 
ferring it from a very dry area to others more and yet more 
humid. 
Geographical variations I therefore accept as sufficient reason 
for the creation of subspecies as long as they are constant within a 
given area, though intermediate areas may be inhabited by inter- 
mediate forms. 
Broadly speaking, in giving geographical forms the status of sub- 
species, I have acted upon the following lines: When I have found 
differences in the plumage or in the size of birds, inhabiting different 
areas, which are quite plain to anyone’s observation, I accept them as 
