118 THE PRESIDENTS ADDRESS. 
following out the suggestion of Agassiz as to the correspondence of 
different species of men with the natural geographical areas of the 
animal kingdom, divide the globe into eight zoological realms, through- 
out which their human fauna are distributed under forty-three 
different heads; and it is by no means apparent that this is an 
exhaustive division into species of the genus homo. 
Looking to the tendency of such views to an ever-widening multi- 
plicity of species, or races of men, and to the consequent diminution 
in a corresponding ratio, of the elements of difference between them, 
it is impossible, I conceive, to overlook the force of some of Darwin’s 
arguments in their bearing on this momentous question. Take, for 
example his favourite illustration, the domestic pigeon ; we look in 
vain for the slightest trace of the transmutation of a bird of another 
genus into any one of the varied and widely-scattered breeds of the 
wild or domestic pigeon, whatever force we may recognise in the 
arguments by which he traces all alike back to the Columba livia. 
Pigeons, he shows, have been domesticated for thousands of years. 
Lepsius indicates the record of them on the monuments of Egypt in 
the fifth dynasty, some three thousand years before Christ; Birch 
traces them in an Egyptian bill of fare of a still earlier date; Pliny 
refers to their extravagant cost among the luxurious Romans ; Akber 
Khan maintained them by thousands ; and the monarchs of Iran and 
Turan deemed them fitting gifts for the lordly Sultan. The same 
wild breed of pigeons has been found capable of domestication in 
northern Europe, and in India, and is seen to agree in habits and in 
numerous points of structure with all the domestic breeds; yet, says 
Darwin, ‘‘although an English carrier or short-faced tumbler differs 
immensely in certam characters from the rock-pigeon, by comparing 
the several sub-breeds of these breeds, more especially those brought 
from distant countries, we can make an almost perfect series between 
the extremes of structure.’’ Finally he adds: “It is also a most 
favourable circumstance for the production of distinct breeds, that 
male and female pigeons can be easily mated for life.” But we have 
only to remember that those, and all the other elements referred to, 
are to a far higher extent characteristic of man. Domestication and 
a social settled life, the permanent mating in pairs, the migration in 
communities, the external influences of an artificial civilization and 
highly diverse climatic influences for thousands of years, have all 
pertained to his normal condition, and may all therefore be made to 
