IN DAMP AIR ONLY. 265 



and though the course of a ship through the water 

 may be impeded by the seaweed on its bottom, that 

 weed does not tend in any way to injure the timber. 

 As there are no sea animals which breed maggots in 

 the dead bodies of land animals that find their way 

 to the sea, so there are not in the sea any parasitical 

 plants which hasten the decay of land plants there. 



There is another proof in the peat bogs : when 

 trees fall through decay, in damp and rainy situa- 

 tions, and it is only in such situations that they de- 

 cay at the surface of the ground, there are generally, 

 if not always, successions of fungi around the root 

 of the tree for several years before it becomes so 

 weakened as to yield to any thing but a flood or a 

 tempest. When the tree does fall, it is usually cov- 

 ered with fungi on those parts against which the 

 water forms a damp, but not where it forms a pool. 

 In that case, the fungi will be at the surface of the 

 water; and if the trunk is altogether under water 

 there will be none. But even where the fungi do 

 appear, they are not of long continuance. Their 

 soft glutinous substance, which is soon gone in the 

 ordinary seasonal crop, unites with the mud which 

 the rains of autumn, after the season of the fungi is 

 over, collect, and the two form a water-tight paste 

 by which the slope towards the tree is converted into 

 a little dam. There are abundance of the germes 

 of the fungi, in the matter of these dams, although, 

 in that stage, even those of the larger species are 

 not visible until they have arrived at that period of 

 their underground growth in which those of the 

 esculent mushrooms are known by the name of 

 spawn. Yet though they are there, they never ger- 

 minate, if the water continues, nor would they do so 

 if the place were to become quite dry. But the 

 water brings another tribe, the mosses, the germes 

 of many of which are as invisible when alone (and 

 when with the plants their existence may be said 

 to be inferred rather than seen) as those of the 

 Z 



