288 STUDIES OF AMERICAN FUNGI. 



Into a bowl put one cup of soft bread crumbs ; season it with a half 

 teaspoonful of salt and a dash of pepper ; pour over a tablespoonful 

 of melted butter ; heap this over the top of the tomato, forming a 

 sort of pyramid, packing in the mushrooms ; stand the tomatoes in a 

 baking pan and bake in a moderate oven one hour. Serve at once, 

 lifting them carefully to prevent breaking. 



Or, the mushrooms may be chopped fme, put with a tablespoon- 

 ful of butter into a saucepan and cooked for five minutes before they 

 are stuffed into the tomatoes ; then the bread crumbs packed over 

 the top, and the whole baked for twenty minutes. Each recipe wil 

 give you a different flavor. 



CHAPTER XXII 



CHEMISTRY AND TOXICOLOGY OF MUSHROOMS. 



By J. F. CLARK. 



Regarding the chemical composition of mushrooms, we have in 

 the past been limited largely to the work of European chemists. 

 Recently, however, some very careful analyses of American mush- 

 rooms have been made. The results of these investigations, while 

 in general accord with the work already done in Europe, have em- 

 phasized the fact that mushrooms are of very variable composition. 

 That different species should vary greatly was of course to be ex- 

 pected, but we now know that different specimens of the same species 

 grown under different conditions may be markedly different in chem- 

 ical composition. The chief factors causing this variation are the 

 composition, the moisture content, and the temperature of the soil in 

 which they grow, together with the maturity of the plant. The tem- 

 perature, humidity, and movement of the atmosphere and other local 

 conditions have a further influence on the amount of water present. 



The following table, showing the amounts of the more important 

 constituents in a number of edible American species, has been com- 

 piled chiefly from a paper by L. B. Mendel (Amer. Jour. Phy. I : 

 225-238). This article is one of the most recent and most valuable 

 contributions to this important study, and anyone wishing to look 

 into the methods of research, or desiring more detailed information 

 than is here given, is referred to the original paper. 



