324 



PRACTICAL COURSE IN BOTANY 



FIG. 457. 



under the microscope and notice that it is 

 composed of delicate filaments made up of 

 single cells placed end to end, as in Spi- 

 rogyra (341). These filaments are called 

 hyphce. 



370. The button. Look on the my- 

 celium for one of the small round bodies 

 called buttons (Fig. 457). These are the 

 beginning of the fruiting body popularly 

 known as the mushroom, and are of va- 

 M ceiium r i us si zes > some of the youngest being 

 of a mushroom (Agaric^ barely visible to the naked eye. After a 



campestris) , with young , . ,-, i , i -i -, 



buttons (fruiting organs) tim e they begin to elongate and make 

 in different stages : i, 2, their way out of the substratum. 



3, 4, 5, sections of fructi- 



fication at successive pe- 37i. The veil and the volva. Make a 

 riods of development; m, ver ti ca l section through the center of one 



mycelium ; st, stipe ; p, 



piieus ; i, gill, or lamina ; of the larger buttons after it is well above 

 Vf vei1 ' ground, and sketch. Notice whether it is 



entirely enveloped from root to cap in a covering membrane 

 - the volva (Fig. 458, a) or 

 whether the enveloping mem- 

 brane extends only from the 

 upper part of the stem to the 

 margin of the cap the veil (Fig. 

 458, d) ; whether it has both veil 

 and volva, or finally, whether it 

 is naked, that is, devoid of both. 

 372. The stipe, or stalk. - 

 Notice this as to length, thick- , / 

 ness, color, and position; that is, 

 whether it is inserted in the 

 center of the cap or to one side 

 (excentric), or on one edge (lat- 

 eral). Observe the base, whether FlG 4 58. Diagram of unex- 



bulboUS, tapering, Or Straight, panded ^mont'to, showing parts: a, 



volva ; 6, piieus ; c, gills ; d, veil ; e, 



and whether surrounded by a s ti pe ; m, mycelium. 



