ON MUSBURY CASTLE. 65 



rest for support, so in the broader world of 

 plant and animal life upon the castle here 

 there is always a fairly fixed number of 

 species and individuals, all fitting in together 

 into the marvellously complicated scheme of 

 checks and counter-checks, of mutual services 

 and reciprocal needs. There are always just 

 enough bees to fertilise the heather, and just 

 enough heather to feed the bees, hedgehogs 

 to keep down the wire-worms, and dragon- 

 flies to chase the gnats. In every bit of 

 boggy ground you find boggy plants ; and 

 above them you find bog-haunting insects, on 

 which the waterside birds perpetually prey. 

 Wherever there is a chance for a plant or 

 animal to make a living for itself, there you 

 find some creature living and adapted to its 

 place. No nook in nature is too small or in- 

 considerable to be occupied. Countless seeds 

 and eggs and germs are being scattered 

 broadcast over the whole face of the earth 

 every day and all day long; and those of 

 them which find their fitting place live and 



F 



