TOADSTOOLS AND THEIR KINDRED. 



131 



perform functions, by which they are allied to all other plants and 

 closely related to one of the largest groujjs of the vegetal kingdom. 

 They stand, in fact, at the head of the class of fungi, of which there 

 are at least as many species as of all flowering plants put together. 



These singular forms, though low in the scale when compared with 

 the green and blossoming world around us, are yet complex and im- 

 posing when contrasted with the world of plant-life revealed by the 

 microscope. They have a distinct vegetative system, and a highly- 

 organized reproductive system. On examining tlie common cultivated 

 mushroom, a species which grows wild in meadows and pastures, these 

 separate systems may be readily distinguished. The vegetable mould 

 or decaying substance on which it grows is penetrated with grayish- 

 white delicate interlacing filaments which are represented by the root- 

 like fibres shown in Fig. 1 . This w^ebby mass constitutes the vegetative 

 portion of the plant. It is called the mycelium, or, among dealers, 

 the spawn, as by its means the plant is propagated in cultivation. In 

 a dry state it may be kept dormant for a long time, and wall grow into 

 a perfect plant under the influence of heat, moisture, and other favor- 

 ing conditions. 



From this mycelium arises the reproductive system that portion 

 of the mushroom which is seen above-ground and which may be com- 

 pared to the inflorescence of higlier plants. It consists of the long 

 thick stem or sti^ye and the umbrella-like toj?, called the cap or pileus. 

 On the lower surface of this cap vertical plates are seen radiating 

 from the stem, though not connected with it. These plates are known 

 as gills, and in a living specimen they will be found covered on all 

 sides by a delicate membrane called the hymenium. Upon this 

 hymenium are borne the reproductive bodies or spores, which are 

 analogous to seeds. 



Fig. 2. Mushroom in Process of Growth. 



To make our conception of the structure of this mushroom more 

 complete, we will trace its growth from the beginning. The first vis- 

 ible portion is the mycelium, at certain points of which there appear, 

 at an early stage, round tubercles not larger than a mustard-seed, 

 which rapidly increase in size, push through the soil, and become more 

 or less elongated, resembling the shaded cut in Fig. 2. There is yet no 

 external sign of cap or gills, but a section of the tubercle will reveal 



