98 THE COURTSHIP OF ANIMALS 



mates. A dozen times in succession he will break the 

 stillness of the forest gloom with a loud, " How-how, how, 

 how, how ! " Sooner or later comes a responsive, " How- 

 owoo, how-owoo ! " and in a short time, guided by the 

 sound, one or more females discover the object of their 

 quest. But the pairing desire has not yet reached its 

 full intensity, and doubtless to kindle this the display just 

 described is enacted, and not once, but a dozen times 

 probably, before the desired state of frenzy has been 

 aroused. Not seldom another male answers the cry, 

 and this inevitably leads to a duel whereby the fittest 

 and strongest male is speedily discovered. 



A word as to these ocelli. This pattern is rare among 

 birds, and Darwin brought to light some extremely 

 interesting facts regarding it. He was led to investigate 

 the matter by his curiosity as to the meaning of the notch 

 in the ocelli of the Peacock's train-feathers. At last he 

 noticed that among the different species of Peacock 

 Pheasants there was one {Poly pie ctr on chinquis), in which 

 the ocelli were paired, one lying on either side of the 

 shaft, in another (P. malaccense) these approached 

 and partly fused with one another. Now, to get the 

 indented ocellus of the Peacock, we have only to imagine 

 the fusion of two such ocelli, whose long axes inclined 

 obliquely to one another, to get the " eye " of the Peacock 

 with its indented lower edge ; for such fusion would give 

 a continuous upper and an indented lower border. 



The " eyes " of the Argus Pheasant are more interesting 

 still, for, as Darwin pointed out, these have the appearance, 

 if the feathers are held more or less vertically, of a number 

 of balls lying each within a socket, or cup : for each of 

 these balls has a light area which exactly simulates the 

 light glancing across the upper pole of a sphere, leaving 



