96 WILD NEIGHBORS CHAP, in 



quills of the tail of the European porcupine, under 

 circumstances of alarm, is another interesting fact 

 discussed in Chapter VII. 



But the large part the tail plays in the expres- 

 sion of brute emotions, .from furious anger to 

 extravagant joy, is familiar to most persons and 

 need not be dwelt upon here. Mr. Darwin has 

 treated of it extensively in his capital book " The 

 Expression of the Emotions." Foxes, wolves, 

 jackals, et id omne genus, exhibit excitement and 

 alarm by elevating or depressing their brushes, 

 and no doubt wag them in welcome to their 

 friends. The nervous organization and moral sen- 

 sitiveness of dogs have been greatly enhanced by 

 their long association with man, and domestic 

 dogs have many more emotions to express, no 

 doubt, than their wild, or semi-wild, congeners. 

 I have been struck by the lack of affectionate 

 demonstrativeness among the yelping and often 

 savage dogs about an Indian camp. It was rare 

 that any of them were made pets of, and they had 

 never been led to show that welcome and grati- 

 tude and joy which are so plainly expressed by 

 the flexible tails of the terriers, and poodles, and 

 collies of our houses. 



