116 TYPE STUDIES 



119. Pore and tooth fungi. Study representatives of the pore or tooth fungi 

 in the field. Note whether they are parasites or saprophytes. 



A. Observe their form, attachment, and relation to the substratum. 

 Examine some of the bracket types with reference to their position 

 in relation to the surface of the earth. What must be the determin- 

 ing influence in shaping their manner of growth ? Make habit sketches. 

 These structures are fructifications. Where is the vegetative mycelium ? 



B. Note the fruiting surface, or hymenium, lining cylindrical pores in the 

 pore fungi (Fam. Polyporaceos) and distributed over teeth in the tooth 

 fungi (Fam. Hydnacece). Cut into the fructifications to ascertain the 

 structure and position of the pores or teeth. Draw in detail. 



120. Agaricus, Coprinus, Amanita, or other gill fungus * * (App. 

 17). Study the type wien possible in the field. Is it a sapro- 

 phyte or a, parasite ? The toadstool is a fructification. Where is 

 the vegetative mycelium ? Dig up the earth around the base of 

 the toadstool and wash carefully. Examine the white strands of 

 the mycelium under the microscope. Are they single hyphae ? 



A. The fructification. Note the three parts always present in 

 a toadstool : (1) th.e stalk, or stipe; (2) the cap, ovpileus; 



(3) the gills, or lamellce, on the under side of the cap. In 

 addition to these parts there are present in certain genera 



(4) either a cup or volva, or both, from the interior of 

 ■which the stalk rises, and (5) a ring around the stalk just 

 beneath the cap. The ring is the remains of a veil, present 

 at a certain stage of development, connecting the margin of 

 the cap with the stalk. Portions of the volva are found in 

 some forms as scales on the top of the cap. Show these 

 structures in a habit sketch. 



1. Examine in some detail the position of the gills on the 

 cap, their color and texture, and also that of the stalk. 

 Divide the toadstool lengthwise to determine these points. 



2. Section the gills in pith or study sections cut with a microtome 

 (Sec. 212). Note the structure of the fruiting surface, or hymenium, 

 containing basidia, each of which develops four spores, basidiospores, 

 on short stalks, sterigmata. The common mushroom of the market, 

 Agaricus campestris, develops only two spores on each basidium. 

 Observe the relation of the basidia to a network of hyphse in the 



