2370 Journal of Applied Microscopy 



on a piece of bread or other cooked food by keeping it for several days in a 

 closed dish and in a warm, moist air. Several common moulds are sure to ap- 

 pear under such conditions, and will serve to illustrate the appearance and 

 growth of this mycelium. In the case of the larger fungi the mycelium often 

 forms quite large strands or felt-like sheets of interwoven threads, and later 

 these may give rise to the fruiting part of the fungus in the form of a mushroom. 



Fungi are reproduced by means of microscopic cells called spores, which 

 are produced in immense numbers on the mature or fruiting part of the fungus. 

 These spores are so light and small that they float readily in the air and are 

 spread or disseminated in this manner. By squeezing a dry puff-ball a little cloud 

 of smoke-like spore dust is given off and if a little of this dust be examined with 

 a powerful microscope the spores may be observed. 



When the spores of fungi are surrounded by favorable conditions of moisture 

 and heat they will germinate by pushing out a minute tube, which by continued 

 growth and branching forms the mycelium. 



COLLECTING FUNGI. 



In collecting those fungi which live as parasites on other plants, it is custom- 

 ary to take a portion of the affected plant, called the host plant, and dry it care- 

 fully, usually in a plant press, making notes as to date, locality, host plant, and 

 collector. Thus pieces of diseased stems, leaves, and fruits may be collected 

 and later examined for the name of the fungus. This work, however, requires 

 the use of a compound microscope and some training in its use, consequently 

 these suggestions will apply mostly to the collecting and studying of the larger 

 fleshy fungi. 



The most favorable time for collecting these fungi is during the warm, rainy 

 weather of spring, summer, and autumn. A few kinds may be found even in 

 winter when the temperature rises above the freezing point, but these are con- 

 fined principally to decaying logs and stumps, or the trunks of trees. Some 

 kinds occur in dooryards and pastures or along the road side, while a few thrive 

 in gardens and cultivated fields, but the majority are to be sought for in rich, 

 moist woods and in grassy openings in such woods. 



Some arise from soil where the mycelium has been growing unseen for a long 

 time ; others spring up at the base of stumps and trunks, while many thrust 

 themselves out on the surface of some old log, fallen branch, or dead tree, and 

 many kinds find a natural mushroom bed in the decaying leaves of the forest. 

 For collecting fleshy fungi only a few simple tools are needed. A market bas- 

 ket with several small tin or pasteboard boxes, for the smaller specimens, and an 

 old butcher knife or small trowel for lifting them from the soil or prying them 

 from logs, will suffice ; care should be taken to secure all parts of those kinds 

 which grow on the ground. Thus they should be lifted by digging under the 

 base of the stem, and not pulled up. Specimens intended for study should be 

 carefully handled so as not to break or rub them. The woody kinds which grow 

 on decaying timber can usually be dried at once and studied later, although it is 

 desirable to secure some of the spores in the form of a spore-print, described 

 later. The more perishable kinds should be studied in as fresh condition as 



