164 



PRACTICAL BOTANY. 



9. Make sections of the pileus so as to obtain transverse 

 vertical sections of the lamellae. A Toadstool just ready 

 to open should be used. Examine a 

 lamella under high power. The cen- 

 tral portion is the trama; compare its 

 structure with the structure of the stipe. 

 Outside of the trama are the subhyme- 

 nium and the Tiymenium. Projecting 

 from the hymenium are the basidia, 

 large cells having pointed extensions on 

 the outer ends. In some cases the spores 

 FIG. 95. A portion will be found still attached to these 

 show^g^tifman! P oints 5 in other cases they will have 

 ner in which the fallen off. What is the shape of the 



a P and S th a e ie ceiis r be- s P ores ? These spores are sometimes 

 low it are cells of called basidiospores, from the manner in 



the trama; b is aba- i i j_i i r _< , i 



sidium; c, spores; wnich the J are borne. They are of the 

 the cells projecting type known as gonidia. Between the 



upward between , .,. .. ., .. ,, .., 



the basidia are basidia notice the projecting cells with 

 paraphyses. (After round ends ; these are paraphyses. Draw 

 a portion of the lamella, showing all the 

 parts seen. (See Fig. 95.) 



II. The Tube-bearing Toadstools {Polyporieoe}. The 

 members of this group are also easily recognized. They 

 have the general umbrella shape of the gill-bearing forms, 

 but in place of the gills are numerous tubes arranged verti- 

 cally and parallel to one another. The commonest forms 

 belong to the genus Boletus. This genus includes many 

 poisonous species and a few highly prized edible species. 



THE TUBE-BEAKING TOADSTOOLS. PRACTICAL STUDIES. 



1. Collect as many different kinds of tube-bearing 

 Toadstools as you can find. Compare them as to color, 

 shape, and size of the pileus. Do you find any forms 

 with an annulus? Any with a volva? 



