MUSHROOMS AND TOADSTOOLS 237 



Spawning consists in breaking up the bricks of spawn into about ten 

 pieces and one piece of spawn, which consists of hard manure pene- 

 trated by the mushroom hyphae, is used for each square foot of bed 

 space. The piece of spawn should be covered by about one inch of 

 compost which should have a temperature of 70° to 75°F. The casing 

 soil should be well moistened by repeated sprinkhng, and not by a sud- 

 den drenching. Under favorable conditions, such a bed should come 

 into bearing in from six to eight weeks after spawning, and during the 

 period of production constant care in the matter of watering is neces- 

 sary to keep the beds up to the maximum conditions of production. 

 The making of spawn is an art in itself and the process is fully described 

 in a recent book by B. M. Duggar on "Mushroom Growing," published 

 in 191 5 by Orange Judd Company, New York. Duggar also ascer- 

 tained in his studies of the mushroom that fragments of growing mush- 

 rooms obtained under aseptic conditions could be made the starting 

 point for pure cultures of spawn. This is based on the fact, that a 

 small piece of the inner stipe tissue of a fresh mushroom will, when 

 placed on any suitable sterile nutrient medium, promptly develop a 

 mycelium. The method of making pure cultures is described in Bulle- 

 tin 85, Bureau of Plant Industry, United States Department of Agri- 

 culture and in Duggar's "Mushroom Growing" and need not be re- 

 peated here. 



Chemistry and Toxicology of Mushrooms. — With the increase 

 in the cost of hving and in our population, which is beginning to feel the 

 shortage of food supplies, earnest attention has been directed to foods, 

 such as the edible wild fungi, which are frequently abundant during the 

 summer months. One phase of this study has been the investigation 

 of the food value of mushrooms and toadstools. Chemical analyses 

 have been made to ascertain what they contain. It has been found, 

 that such a fungus as Polyporus sulphureus, has over 70 per cent, of 

 water, while species of Agariciis and Coprinus have fully 90 per cent, 

 of water. As to nitrogen, although the proportion of this element in 

 the dry matter of different fleshy species varies from 2 to 6 per cent., it 

 has been found that much of the nitrogen is present in the form of non- 

 protein substance of a very low food value and some of it enters into 

 the composition of a substance closely related to cellulose. Thus, not- 

 withstanding the fact that Coprinus comatns contains 5.79 per cent, of 

 nitrogen, we find only 0.82 per cent, as available (digestible) proteins, 



