CH. XXVIII. WOOD-PIGEONS. 139 



subject to a kind of cancer and growth on their 

 bills and about the eyes, which eventually destroys 

 them ; but I attribute this disease to feeding on 

 the beech-mast, which is probably too heating a 

 food for the young birds. The old wood-pigeons 

 are seldom if ever attacked by this disease, not- 

 withstanding their great fondness for beech-mast 

 and acorns. 



Wood-pigeons are not so much valued for the 

 larder as they deserve to be. They are excellent 

 eating at all seasons, excepting when driven by 

 snow to feed on the turnip leaves. Since the de- 

 struction of vermin and the increase of fir planta- 

 tions, they have grown very numerous in many 

 parts of the country, where, a few years ago, they 

 were comparatively rare. It is, however, difficult 

 to kill many of them during the winter and 

 autumn, when they are collected in flocks, their 

 safety resulting rather from their timidity than 

 from any excess of cunning. 



Most birds, while feeding in flocks, appoint sen- 

 tinels, whose duties appear to be perfectly under- 

 stood, as well by the guards as by the guarded : 

 red-deer, too, whilst resting, usually place a young 

 stag as sentinel, and do not allow him to lie down 

 or leave off his vigilant watching, which often lasts 

 a considerable time. Those at rest appear to be 



