THE PLAY OF ANIMALS. 251 



be calculated to inspire fear, such as erection of the 

 feathers, etc., but even exhibitions of flight and sing- 

 ing. Canaries commonly trill shrilly while fighting, 

 and Brehm says that the lapwing, which is very irrita- 

 ble during the nesting period, becomes wildly excited, 

 sounds his mating call, and tumbles about in the air 

 at the approach of a man or an animal. Since, then, 

 the excitement of anger can produce these effects re- 

 flexly, it is probable that that of courtship may fre- 

 quently act in the same way; indeed, among the lower 

 orders this is probably the rule. 



On the other hand, we are forced to remember that 

 the acts of the higher animals are generally accom- 

 panied by quite complicated psychic processes. Tak- 

 ing birds again as our example, it must be conceded 

 that an enlightened animal psychologist is obliged to 

 attribute to them a highly developed intellectual and 

 emotional life. " Adequately to treat of the intelli- 

 gence of birds," says Romanes, "a separate volume 

 would be required." * And we know from many in- 

 dependent observations that are mutually confirmatory 

 to a remarkable degree that this statement is not exag- 

 gerated. Pigeons recognise a voice after many months' 

 absence, and a bullfinch belonging to one of the Miillers 

 did so after nearly a year.f Tame storks answer to a 

 familiar name. J It is well known that birds dream, 

 and parrots sometimes talk in their sleep; the emotions 

 of love and sympathy are very active; the conjugal 

 fidelity of many species speaks for the finer feelings, 

 the wedded pair evincing the deepest grief on being 



* Animal Intelligence, p. 266. 



t A. and K. Muller, Thiere der Heimath, i, p. 114. 



X Naumann, ix, p. 256. 



