XXII. ANIMALS' ILLUSIONS 



A CURIOUS instance of animal illusion was seen on the 

 Thames last summer by those on their way to Henley 

 by river. A cock swan was fighting his own reflection 

 seen in the window of a partly-sunken house-boat, 

 which acted as a looking-glass. He had been doing 

 battle for some time in defence, as he supposed, of his wife 

 and family, who were grouped together close by, and had 

 apparently begun to have some misgivings as to whether 

 the enemy were real or not, for at intervals he desisted 

 from the attack, and tapped the frame of the window 

 all round with his bill. 



Birds are perhaps more commonly the victims of 

 illusions than other animals, their stupidity about their 

 eggs being quite remarkable. Recently, for instance, a 

 hen got into the pavilion of a ladies' golf-club, and 

 began to sit in a corner on a golf-ball, for which it 

 made a nest with a couple of pocket-handkerchiefs. 

 But many quadrupeds are not only deceived for the 

 moment by reflections, shadows and such unrealities, but 



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