SPIRIT OF UNREST 185 



rushing and wheeling about the air for some time, 

 return once more to the resting-place. 



This same spirit of unrest, or of a " state of nerves," 

 was observable in a majority of the migrants, and 

 manifested itself in an increasing wildness; in signs 

 of suspicion or fear, and extreme readiness to take 

 alarm at slight causes which would not have moved 

 them a short time before. They were like the bird 

 population of a marsh or copse or plain where a hawk 

 has suddenly descended to strike down and carry 

 one of them off. The excitement was not so acute, 

 but it did not pass away in a little while to leave 

 them at peace, as after the raid of a falcon; it 

 continued from day to day, and increased till the 

 moment of going. 



This spirit of unrest was not visible in all the 

 migrants; it was most marked in the most volatile 

 species, the swiftest of wing and wildest; in others 

 in a less degree, down to those in which it was not 

 noticeable. There were, in fact, with regard to this 

 as well as to other emotions which birds experience, 

 demonstrative and undemonstrative species. 



The differences in behaviour here are similar to 

 those we see in the manifestations of parental solici- 

 tude. Many species, when the nest with eggs or young 

 is in danger, are excited in a violent degree; they 

 scream their loudest, and in some instances are so 

 carried away with anxiety and rage that they will 

 attack any animal, however dangerous, or man him- 

 self, as I have been attacked in South America again 

 and again by plover, by hawks, and even by small 



