General Features 27 



has been evolved from a coprophilous species, the spores of 

 which having been planted on the ground, stimulated by the 

 heat of the fire, and supplied with a suitable nutrient medium 

 released by the heating of the soil, grow and become adapted 

 to this habitat. It differs from Pyronema which it resembles in 

 habitat by the fact that the spores of the latter do not require 

 the heat stimulus to induce germination. 



17. Viability of the Spores 



The length of time the spores of the cup-fungi will keep their 

 viability probably varies greatly with different species. The 

 writer has not carried on any extensive observations along this 

 line but the one species Pyronema omphalodes has been experi- 

 mented with and the spores found to keep their viability for 

 nearly three years in an ordinary herbarium packet in the 

 herbarium. How much longer they might have retained their 

 power to germinate has not been determined. 



This fact ought to be of especial interest to those who are 

 interested in keeping this fungus on hand for cultivation in 

 class use. 



18. Mycophagy * 



The majority of the operculate cup-fungi are too small to be 

 worthy of consideration as articles of diet. Many of the larger 

 species are recommended by mycophagists and are used when- 

 ever they can be found in sufficient quantity. None, so far as 

 the writer knows, are decidedly poisonous although one species 

 has been under suspicion. This is the so-called Gyromitra 

 esculenta (Fig. 15) which the writer here regards as merely a 

 gyrose form of Elvela infula, at least so far as our American 

 forms are concerned. It is interesting to note that this form 

 which was originally designated as " esculent " should be the 

 first one to be brought into disrepute. Of course our American 

 form may be different from the European which goes under the 

 same name. Some mycophagists claim to have eaten it without 

 the slightest discomfort but, if used at all, one should proceed 

 very cautiously. 



Probably the most valuable species from the culinary point 

 of view is MorcheUa esculenta, more commonly known as the 

 " common morel," the " spring mushroom " or the " honey- 

 comb fungus." In the northern states this species occurs almost 

 exclusively in the month of May, hence the name spring mush- 



