MUSHROOMS 161 



eye can observe. The roots of many trees are closely 

 wrapped in fungus ; and without the fungus they would 

 scarcely be able to suck nutriment from the soil. The 

 fungus tribe indeed, including bacteria, alone have the 

 power to transmute the soil into food for the plant. The 

 trunks and boughs of the trees in these wetter districts are 

 blue and green with lichens, the most curious of all the things 

 that grow ; an old wonder to the botanists. The lichen will 

 stay shrivelled and unmoving for a thousand years, and then 

 wake again, with Rumpelstilzchen vigour, to a new life. It 

 possesses this persistent hold on life, it can suck nutriment 

 from a stone ; and yet it is killed more easily by foul air than 

 any plant. No lichen has been discovered, save one small 

 patch on stucco, within the circle of London smoke. The 

 lichen is not all fungus ; but half fungus, half alga ; and the 

 two are joined together in an inextricable copartnership, each 

 flourishing with the other's help. In the wetter west the 

 lichens hang in quaintly twisted plaits of green and grey and 

 brown, giving every tree and rail a dank and mouldered air, 

 though beautiful withal. In the drier east and within range 

 of a town they dwindle to almost dusty disks. You may tour 

 the better part of Epping Forest and scarcely find an 

 example. 



Like small and unpleasant animal parasites each fungus 

 has a close affinity with a particular host, whom, in many 

 cases, it eats out of hearth and home. Watching the tits 

 busy one autumn day along the larch boughs, one notices 

 a twig of needles that have paled before their time. The 

 fungus, which is the ruin of new forests clothing the catch- 

 ment areas of the Lakes, has begun to take its hold ; and the 

 tree is doomed. In happy England no disease rages with 

 extreme virulence ; larches may suffer, but they are not wiped 

 out. 1 1 is different in America. Within the early years of this 



