98 LABORATORY AND FIELD KXKKCISKS 



b. Examine mushrooms of different ages. Is the color of 



these plates, or gills, the same in young anil in old 

 specimens ? Compare the color change which you 

 observe with that of molds. What is the function or 

 use of the plates, or gills ? 



c. Bisect a mushroom vertically through the umbrella and 



its stalk. Study the relation of the gills to the umbrella. 

 Draw the cut surface of the mushroom and include the 

 subterranean and the aerial parts. (The subterranean 

 portions may be drawn from specially prepared material 

 if they are not available in the laboratory specimens.) 

 liead the paragraph in the text and consult Fig. 147 

 on the parts of the mushroom. Label correctly the 

 parts of your figure showing the habit of the muslin >om. 



3. Nutrition. State concisely the function of each part of 



the mushroom drawn above. Indicate the income and 

 the outgo of the mushroom in gases, liquids, and soh'ds 

 in connection with the above figure or in an outline 

 figure similar to Fig. 2, Part I, of text. 



4. Growth and expansion of mushrooms. Study a series of 



mushrooms of different ages. "What changes in the 

 size, form, and relation of parts do you find taking place 

 in mushrooms from young to mature stages \ What is 

 the apparent function, or use, of these changes ? Praw 

 a series of diagrams to illustrate the growth stages of 

 a mushroom and discuss briefly the function, or use, 

 of the changes indicated by your drawings. 



5. Structure. Tease out on a slide portions of the stipe of a 



mushroom. Mount and study. Is the mushroom cel- 

 lular like a higher plant, or is it an aggregation of 

 hypha' ? Contrast the structure of a mushroom and 

 that of a mold. Make drawings to indicate the structural 

 elements of the mushroom. 



