SOLITARY AND GREGARIOUS. 39 



a knowledge most probably acquired by the reite- 

 rated experience of having their nesMrees fired at 

 when the young are fit to be made into pies. It is 

 stated in some accounts of newly-discovered countries, 

 that the birds were not at first frightened by the pre- 

 sentment of a fowling-piece, but soon became so 

 after some experience of its effects. We also think 

 it not unlikely that the crows acquire part of the 

 skilful vigilance whicli they exhibit as sentinels during 

 the building of their nests, when one of a pair 

 usually watches the nest while the other makes 

 excursions to procure materials*. 



Our observations by no means bear out what is 

 recorded of rooks being so determined to keep their 

 associates together, that " if a pair offer to build 

 on a separate tree, the nest is plundered and de- 

 molished at oncef." On the contrary, we do not 

 recollect ever observing a rookery without seeing 

 one or more nests on detached trees, sometimes at 

 some little distance from the main establishment. In 

 the rookery at Lee there were, in the summer of 

 1831, two such nests, each on a detached tree, 

 which, we are certain, were not molested during the 

 season J. 



The sentinels of gregarious birds were observed 

 by the ancients, and legends told of them no less 

 exaggerated than those of our modern crow-courts. 

 The crane, in this respect, the most celebrated 

 bird among the ancients, was placed, by Aristotle, 

 at the head of gregarious birds ; and Festus, the 

 grammarian, is of opinion that the words congruous 

 and similar derivatives are from Grues, the Latin name 

 (Grus) of the crane||. u The cranes," says Aristotle, 



* J. R. f Bingley, Anim; Biog. ii. 240. 



$ J. R. Hist. Anim. viii. 12. 



|] "Congruere," says Festus, "quasi ut grues conveniere." 

 De Significatione Verborum, ex Verio Flacco. 



