OF SELBOENE. 121 



a snapping or cracking, pursuing people along the hedges 

 as they walk : these last sounds seem intended for menace 

 and defiance. 



The grasshopper-lark chirps all night in the height of 

 summer. 



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 kestril in churches and ruins. 



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

 of Ely. 1 The threads sometimes discovered in eels are 

 perhaps their young ; the generation of eels is very dark 

 and mysterious. 2 



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 a 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 siknb about Midsummer, re- 

 assume their notes again in September ; as the thrush, 

 blackbird, woodlark, willow wren, &c. ; hence August 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. 



1 Three species of eels are described and figured in Yarrcll's " History 

 of British Fishes." But see antea, p. 39, note 2. ED. 



2 Eels are infested by several kinds of intestinal worms, which are 

 doubtless the thread-like bodies referred to. The observations made 

 by the late Mr. Yarrell on the reproduction of eels leave little doubt 

 that they spawn like other fishes. ED. 



