DISEASES CAUSED BY FUNGI. 71 



staple food of man. Most of the Fungi which attack living 

 vegetables belong to the lower Orders of the tribe. The 

 spawn, however, of higher species is often fatal to trees and 

 herbaceous plants, by running over the roots and inducing 

 decay. It has been long known that trees would not in ge- 

 neral flourish where others had grown before, and this was 

 attributed to exhaustion of the soil ; it is now, however, ascer- 

 tained that the evil arises from spawn attached to old decay- 

 ing roots. A most striking instance occurred lately in the 

 Gardens at Kew. Two Deodaras were planted before the di- 

 rector's house, within a few yards of each other, under appa- 

 rently similar circumstances. After a time, one of these 

 became unhealthy, and it was suggested that the roots should 

 be examined. A scrutiny in consequence took place, when it 

 was found that an old cherry-tree formerly stood on the 

 same spot, that its roots were covered with spawn, and that 

 this had extended to the roots of the Deodara. The remains 

 of the old cherry-tree were accordingly grubbed up, and the 

 diseased portions of the Deodara removed, and now it bids 

 fair to thrive without any further check. The effect is some- 

 times apparently so sudden, that it is attributed to lightning, 

 the fact being that the exigencies of the plant have been sup- 

 plied by a small portion of the roots which remained in a 

 sufficiently healthy condition to convey nutriment. Herba- 

 ceous plants — as, for instance, strawberries — suffer from the 

 same cause, and it is now matter of certainty, that wher- 

 ever fragments of wood or sticks exist in manure, whether 

 in the garden or field, there is considerable danger. The 

 formidable Larch-rot, which converts the trunks of larches 

 so frequently into hollow pipes, is often attributable to this 

 cause. 



Several Fungi, as PoJyporus squamosus, and other species. 



