LANGUAGE. 253 



are only understood by birds of the same species, or 

 rather we should say same family, for it appears to be 

 a family language, understood reciprocally by parent 

 birds and their young: for the young know the 

 notes of the parents, and the parents those of 

 their own brood, amongst all the young broods of 

 other birds of the same species in the neighbour- 

 hood ; and this they do as distinctly as the ewe 

 knows the bleat of her own lamb, or the lamb the 

 cry of its own mother, amongst a large flock. With 

 regard to the note of alarm birds send forth on the 

 approach of their natural enemies, whether a hawk, 

 an owl, or a cat, we consider it to be a general 

 language perfectly understood by all small birds, 

 though each species has a note peculiar to itself. 

 This note differs in sound from the note of fear or 

 alarm given by them when man approaches near 

 their nests. This last seems confined to particular 

 species ; but this general alarm note (which is under- 

 stood by all small birds), we should call their 

 war-whoop or gathering cry, for it is a true natural 

 slogan*." 



The noisy cackle of jays, the cawing of rooks, and 

 the incessant yelp of sparrows, appear, so far as we 

 can judge, to be partly so many social signals for con- 

 gregating in a particular place, and to be continued 

 after the flock has assembled, either to warn strag- 

 glers to what point they ought to wing their way, or, 

 in the spirit of rivalry which prevails so extensively 

 amongst birds, with the object of outvying each other 

 in loudness of tone. It is remarkable, indeed, that 

 most, if not all, gregarious birds are thus noisy, and 

 differ much in this respect from solitary or sub-solitary 

 birds. If a rook or a sea-gull, therefore, is by acci- 

 dent separated from its companions, it will keep up 



* Brit, Song Birds, Intr. p, 31. 



