21 



The, sporophores grow either on the roots of an affected tree or on 

 the trunk, the former being the usual position. When growing on 

 the ground the pile us is supported on a ver}' short stalk; it is sessile 

 when growing from the trunk. There are usually several shelves 

 which are grown together at the center in the ground form, or grown 

 one above the other in the trunk form (see text figure 1 and PI. I, 

 fig. 1). The whole body varies greatl}" in size. The smallest 

 specimens collected during the past summer were 4 inches (lO^"") in 

 diameter; the largest about 14 inches (35""^). The hjnnenial layer 

 begins to form some three days after the body of the pileus is com- 



Fiu. 1. — Folypuras ncliuxiiiitr.ii Fr. growing on u fallen Fir. 



plete, so that there is always a wide band of sterile h3'phj« on the 

 under side of the pileus during the period that the pileus is growing 

 in width. When this growth stops, the tubes gradually form close up 

 to the edge. The h3'menium when f n^sh is rose colored; when touched 

 or bruised it turns dark red very cpiickly. The bright colors of the 

 3'oung pileus gi'tiduallv give wa\^ to more su)>dued ones as th(^ fungus 

 grows older. A few days after growth has come to a standstill, the 

 spores ripen and begin t(^ bi; discharged. T'hey come off in clouds 

 plainly visible to the naked eye. Slips of glass placed under the 

 pileus and left overnight had so thick a layci- of spores deposited 



