MIGRATING BIRDS 



and then, hear a faint, sudden crack. This will be the Broom 

 at work scattering its seeds by itself. The little pod, when 

 it dries, contracts in such a way that it splits with a sudden 

 explosive pop, and the seeds are sent flying to a distance of 

 three or four feet. This curious fact was observed in 1546 

 by the naturalist Boek. The Whin and many other plants 

 act in the same way, for the dry fruit becomes elastic and 

 coils up spirally, flinging away the seed. 



But here also, on the southern shore of England, we are 

 at a main station of arrival and departure for migrating 

 birds. A landrail or other marsh bird might be flushed in 

 France, and might quite easily cross the Channel with 

 French mud sticking to its plumage. In this mud, or in its 

 crop, there may be seeds or fruits which will be left in an 

 English pond. This method is probably a very important 

 one, for these plants growing in duck-haunted places are 

 amongst the most widely distributed of all. 



Mr. Reid has a very interesting discussion on this point. 

 The crow or rook could quite well cross the British Channel 

 now. In the days when Britain was covered with ice and 

 snow, the gap between the French and the English shore was 

 only half the present width. There was at that time 

 much flat land with oak forest bordering the French 

 coast. 



Mr. Reid shows that it is probable that rooks regularly 

 carry about acorns in the cup, for he found seedling oaks 

 associated with empty acorn husks, stabbed and torn in a 

 peculiar way. " On October 29th of 1895, in the middle of an 

 extensive field, bordered by an oak copse and scattered trees, 

 I saw a flock of rooks feeding and passing singly backwards 

 and forwards to the oaks. On driving the birds away, and 

 walking to the middle of the field I found hundreds of empty 



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