150 THE COURTSHIP OF ANIMALS 



Not so the male. He is yet far from satiated ; in him 

 the sexual fever still burns fiercely, but somehow he seems 

 never to make any attempt to provoke in his mate a like 

 condition, as in the days before brooding began. On 

 the other hand, he does not scruple to savagely pursue 

 every other female who ventures abroad in his neigh- 

 bourhood. So soon as a duck takes wing for a brief 

 relaxation from the arduous work of brooding she 

 is pursued by ten or a dozen already mated males, till 

 at last she is obliged to descend on the water, and with 

 her descend her pursuers, now to mob her without 

 mercy. Commonly at least half of these infuriated males 

 will eventually succeed in treading her ; leaving their 

 victim only after she has become completely exhausted 

 or killed outright. This is no unusual occurrence. On 

 the reservoirs at Tring, where every spring from one 

 thousand to one thousand two hundred pairs congregate 

 to breed, from seven per cent, to ten per cent, of females 

 are annually killed in this way. 



It is just possible, however, that an error may have 

 crept into these observations. One cannot help asking 

 may it not be possible that these pursuing males were 

 actually unmated birds ? The chief argument against this 

 is the fact that there is no sort of attempt to " display " 

 apparent with these birds, simply an overmastering, 

 ravenous desire to satisfy the craving which possesses 

 them. 



Evidence is not wanting that the evolution of pigment 

 intensification and the consequent development of vividly 

 coloured liveries, or the equivalent development of orna- 

 ment, has been accompanied by an inrensification of the 

 reproductive instincts. For there can be no doubt but 

 that the display of species which are conspicuous for 



