52 ADVENTURES AMONG BIRDS 



of wild animals are familiar, is seen in the self-appointed 

 guardian or sentinel of the feeding or sleeping flock. 

 In some mammals it appears in a striking way, as in 

 the guanaco on the Patagonian plains, when one mem- 

 ber of the herd ascends a hill or other high spot to keep 

 watch while his fellows are browsing on the bushes or 

 grazing on the plain below. In some birds the watchful 

 spirit is so powerful that the sentinel and alarm-giver 

 is not satisfied to see only those of his own species obey 

 his warning; he would have every feathered creature 

 within hearing escape from danger. The curlew is an 

 example and has been observed by wild-fowlers swoop- 

 ing violently upon and trying to drive up a duck that 

 had remained on the ground after all the other birds 

 in the place had taken flight. 



Much more could be said on the subject if there were 

 not so many others to be dealt with in this book: 

 probably every wild-fowler, and in fact every close ob- 

 server of the actions of birds who reads this chapter 

 will be able to recall some incident he has witnessed 

 which illustrates this helpful spirit. But I cannot con- 

 clude before giving one remarkable example of a bird 

 or of birds making themselves masters of a flock not 

 with any important purpose as in the foregoing instances, 

 but purely in play, or for fun. I witnessed this inci- 

 dent many years ago, and told it briefly in Argentine 

 Ornithology, but that work is little known and unob- 

 tainable, and I am rather pleased at the opportunity of 

 relating it again more fully in this place. 



The bird was a Vanellus, a lapwing in its shape, crest, 



