MUSHROOMS, EDIBLE AND OTHERWISE 



that do find a favorable resting place, under right conditions, will begin to ger- 

 minate by sending out a slender thread-like filament, or hyphse, which at once 

 branches out in search of food material, and which always forms a more or 

 less felted mass, called mycelium. When first formed the hyphae are continuous 

 and ramify through the nourishing substratum from which there arises after- 

 ward a spore-bearing growth known as the sporocarp or young mushroom. This 

 vegetative part of the fungus is usually hidden in the soil, or in decayed wood, 

 or vegetable matter. In Figure 3 is a representation of the mycelium of the 

 small pear-shaped puff-ball with a number of small white knobs marking the 

 beginning of the puff-ball. The mycelium exposed here is very similar to the 



mycelium of all mushrooms. 



In the pore-bearing genera 

 the hymenium lines the vertical 

 pores ; in teeth-bearing fungi it 

 lines the surface of each tooth, 

 or is spread out over the smooth 

 surface of the Stereum. 



The development of the spores 

 is quite interesting. The young 

 basidia as seen in Figure 2 are 

 filled with a granular proto- 

 plasm. Soon small projections, 

 called sterigma (plural, sterig- 

 mata), make their appearance on 

 the ends of the basidia and the 

 protoplasm passes into them. 

 Each projection or sterigma 

 soon swells at its extremity into 

 a bladder-like body, the young 

 spore, and, as they enlarge, the 

 protoplasm of the basidium is 

 passed into them. When the 

 four spores are full grown they 

 have consumed all the proto- 

 plasm in the basidium. The 

 spores soon separate by a trans- 

 verse partition and fall off. All 

 spores of the Hymenomycetous 

 fungi are arranged and pro- 

 duced in a similar manner, with 

 their spore-bearing surface ex- 

 posed early in life by the rup- 

 ture of the universal veil. 



In the puff-balls the spores 

 are arranged in the same way, 



Figure 4. Small portion of a section through the spore- 

 bearing part of a morel in which the spores are pro- 

 duced in little sacs or asci. (a) An ascus, (b) an 

 ascus discharging its spores, (c) the spores, (d) sterile 

 cells. Highly magnified. Longyear. 



