MISCELLANEOUS OBSEEYATIONS. 187 



Swans turn white the second year, and breed the third. 



Weasels prey on moles, as appears by their being some- 

 times caught in mole-traps. 



Sparrow-hawks sometimes breed in old crows' nests ; and 

 the kestrel in churches and ruins. 



There are supposed to be two* sorts of eels in the island 

 of Ely. The threads sometimes discovered in eels are per- 

 haps their young : the generation of eels is very dark and 

 mysterious. 



Hen-harriers breed on the ground, and seem never to 

 settle on trees. 



When redstarts shake their tails, they move them hori- 

 zontally, as dogs do when they fawn : the tail of the wagtail, 

 when in motion, bobs up and down, like that of a jaded 

 horse. 



Hedge-sparrows have a remarkable flirt with their wings 

 in breeding time : as soon as frosty mornings come, they 

 make a very piping, plaintive noise. 



Many birds which become silent about midsummer re- 

 assume their notes again in September ; as the thrush, black- 

 bird, woodlark, willow- wren, &c. ; hence August t is by much 

 the most mute month, the spring, summer, and autumn 

 through. Are birds induced to sing again because the 

 temperament of autumn resembles that of spring ? 



Linnaeus ranges plants geographically ; palms inhabit the 

 tropics ; grasses the temperate zones ; and mosses and lichens 

 the polar circles : no doubt animals may be classed in the 

 same manner with propriety. 



House-sparrows build under eaves in the spring; as the 

 weather becomes hotter, they get out for coolness, and nest 

 in plum-trees and apple-trees. These birds have been known 

 sometimes to build in rooks' nests, and sometimes in the 

 forks of boughs under rooks' nests. 



* There are three species of eels. See Mr. Yarrell's work on British 

 fishes. Eels are infested with intestinal worms, a circumstance which has 

 induced many to suppose them to be viviparous, myself amongst the rest. 

 The generation of eels is now well ascertained. ED. 



f The robin is the only bird I hear sing in August. They perhaps moult 

 earlier than other song-birds, for in the moulting season birds are perfectly 

 mute. ED. 



There two species of sparrows, the house and the tree sparrow. See 

 Mr. Yarrell's British Birds. ED. 



