SOME COMMON MUSHROOMS AND HOW TO KNOW THEM 6 



as giving out such a clear emerald-green light that reading in the 

 near vicinity is possible. Phosphorescence or luminosity is often 

 observed in dead wood and is due to the presence of mycelium, the 

 threadlike vegetative part of the fungus. This often gives off a 

 bright glow which may be seen from some distance. Phosphores- 

 cence is often exhibited by the mushroom itself, as in the case of 

 CUtoeybe Uludens, commonly known as jack-o'-lantern, and Panus 

 stypticus, a very common and cosmopolitan species. 



While the utilitarian value of mushrooms and certain other fungi 

 is popularly thought to be very limited and mostly restricted to their 

 use as food, there are many other uses, though not of universal prac- 

 tice, which may be mentioned. In early times various species were 

 employed extensively in medicine, though to-day their use is rather 

 restricted. Certain species were used as emetics, purgatives, astrin- 

 gents, or for their styptic property. Although the use of fungi in 

 medicine is more restricted than in ancient times they still play an 

 important role in various industries. Certain species are highly im- 

 portant as fermenting agents and are used in the manufacture of 

 beer, wine, cider, vinegar, saki, alcohol, bread, cheese, and other 

 commercial products. They have also been employed in the arts as 

 tinder and for dyeing silks, cottons, and wool. 



The main discussion of this circular is concerned with the class of 

 fungi known as mushrooms, though a few interesting and conspicu- 

 ous varieties of other groups are considered. The characters of each 

 family or genus are discussed, and then descriptions of the plants 

 belonging to the respective family or genus are given. 



DANGER FROM POISONOUS FUNGI 



On account of the many casualties resulting from the use of fungi 

 as food by persons unfamiliar with the different kinds, an urgent 

 appeal is made to the collector to abstain from experimenting with 

 or eating any mushrooms unless he is absolutely certain of the 

 identity and edibility of the species collected. It is not safe to col- 

 lect young, unopened mushrooms, commonly known as buttons, as it 

 is often difficult to distinguish between poisonous and edible species 

 in the early stages. 



Attention is called to the danger of depending on so-called tests for 

 distinguishing poisonous and edible species. The assertions that 

 mushrooms are poisonous if a silver coin placed in the utensil in 

 which the mushrooms are cooked tarnishes, and that those which peel 

 easily are edible, are wholly erroneous. The presence of insects on 

 fungi is no guide as to their edibility, because insects infest both 

 poisonous and edible mushrooms. The notion that soaking or boiling 

 poisonous mushrooms in salt water will render them harmless has no 

 foundation in fact. 



Although it is quite possible for a person to learn a few common 

 and characteristic mushrooms, this circular in no way guarantees that 

 the reader may be able to distinguish between all edible and poison- 

 ous species, for in order to become thoroughly familiar with the 

 subject, continued study under a competent instructor is absolutely 

 necessary. 



