THE FLOWERLESS PLANTS. 183 



accumulation of soil by their decay, but they actually 

 feed upon the rocks by means of oxalic acid that exudes 

 from their substance. By this process the surface of the 

 solid rock is changed into a soil fitted for the nutrition of 

 plants. After the lichens have perished, the mosses and 

 ferns take root in the soil that is furnished by their decay. 

 One vegetable tribe after another grows to perfection and 

 perishes, but to give place to its more noble successor, 

 until a sufficient quantity of soil is accumulated for the 

 growth of a forest of trees. In such order may the whole 

 earth have been gradually covered with plants, by the 

 perishing of one tribe after another, leaving its substance 

 for the support of a superior tribe, until the work of crea- 

 tion was completed. 



Among the grotesque productions of nature, the fungi, 

 or mushroom tribe, ought undoubtedly to be named as 

 the most remarkable, attaining the whole of their growth 

 in the space of a few days, and sometimes of a few hours. 

 They are simple in their parts, like what may be supposed 

 to have been the earliest productions of nature. They 

 have no leaves or flowers or branches. They will grow 

 and continue in health without light, requiring nothing 

 but air and moisture above their roots. Though so low 

 in the scale of vegetation, they are not without elegance 

 of form and beauty of color, and are remembered in 

 connection with dark pine woods, where, forming a sort 

 of companionship with the monotropas, they are particu- 

 larly luxuriant. Neither are they deficient in poetical 

 interest, as these plants are the cause of those fairy rings 

 that attract attention by their mysterious growth in cir- 

 cles on the greensward in the pastures. 



The mushrooms vary extremely in their forms and 

 sizes. Some are as slender as the finest mosses, tinted 

 with gold and scarlet, and almost transparent. Others 

 resemble a parasol, with their upper surface of a brilliant 



