JANUARY 23 



roots of the heather, which withers away and looks as 

 if it has been seared by frost. No remedy can be sug- 

 gested, for this creature waxes and wanes without any 

 apparent cause. All that we have gained is the know- 

 ledge that if ' frosted heather ' is the cause of grouse 

 disease, temperature has nothing to do with it. The 

 idea which experience encourages is that grouse disease 

 puts in an appearance in places where abnormal repro- 

 duction has raised the stock above the natural limit, 

 whence it may spread by infection to other and less 

 densely populated moors. Five or six years ago, when 

 the vole plague was at its height in the Scottish 

 lowlands, and sheep farmers were at their wits' ends 

 because of their ruined pastures, when every hillside 

 from Ettrick to Carsphairn was alive with the vermin, 

 suddenly the creatures began to rot off in thousands, 

 until the vole population shrank to normal and harm- 

 less proportions. So it is with grouse. In this district, 

 Galloway, there remain many patches of one hundred 

 to one thousand acres of moor and mossland, isolated 

 among wide tracts of arable land. Each of these patches 

 produces annually a few broods of grouse, but these never 

 exceed the power of the ground to sustain them in health, 

 and such a thing as a diseased bird has never been seen. 

 Probably the heather beetle is subject to a similar 

 natural and automatic check. Always present in the 

 soil, some incalculable combination of favourable cir- 

 cumstances causes it to multiply abnormally, until 

 Nature decrees, ' Enough ! too much ! ' and the swarms 

 die off. It is pretty clear that gamekeepers may dis- 



