Bulletin 39, united states national museum. [21] 



(4) Dried speciineus sboiild be soaked first in the fluid or iu brine; a 

 few will bear glycerine. 



(5) Slides of some service for microscopic use may be quickly pre- 

 pared at the shore by drying small specimens or fragments on thin 

 pieces of mica (1 by 3 inches or less), moistened by water when studied. 



FUNGI.* 



SAPROPHYTIC FUNGI. 



The woody fungi found growing like shelves from the sides of old logs, 

 stumps, and trees should not be avoided by the collector since they are 

 the easiest of all specimens to collect. Many of the thin small speci- 

 mens of this sort found on dead sticks may be put in press along with 

 other plants and tied up in the same packages. All the larger and 

 thicker forms may be simply wrapped in paper with their labels tied or 

 pinned on them and packed away in boxes. 



With the moister and more fleshy fungi the difficulties of preserva- 

 tion are very great, so much so that with most of the fungi known 

 popularly as mushrooms and toadstools it is simply impossible to make 

 satisfactory herbarium specimens. Some of the species are gelatinous. 

 Others break down into a jelly a few hours after maturity. With all 

 these extremely fleshy species the only way to preserve their form and 

 color is to make colored sketches soon after collection. These with the 

 spores saved on paper will help make up the deficiencies of the speci- 

 men. The spores are saved by cutting off the cep from its stalk and 

 laying it on a sheet of white paper with the gills down. Inafew hours 

 the paper will be found covered with the spores. If the gills are light- 

 colored black paper may be used, as light-colored spores will be more 

 readily seen on it. The best way to preserve the specimens themselves 

 is to dry them out in the sun or with artificial heat properly regulated. 

 Under this treatment the more leathery ones will retain their form and 

 color fairly well, but the putrescible species will not amount to much. 

 After the specimens are thoroughly dry they may be exposed to damp 

 air either in a box or out of doors in the evening, and while so softened 

 put under pressure for a day or so. Do not sprinkle water on the spec- 

 imens. The object is simply to dampen them enough to take away their 

 brittleness. It is not necessary to press these dried specimens. They 

 may be simply wrapped in paper and packed into boxes. 



PARASITIC FUNGI. 



The various kinds of parasitic fungi known commonly under the 

 names of rusts, smuts, mildews, blights, etc., are important objects for 

 thecollector. While many thousands of species have been described 

 from various parts of the globe new ones are continually being found 

 even in the best studied regions. Extensive collections in almost any 



By M. B. Waite, assistant mycologist U. S. Departiiieut of Agriculture. 



