440 



THE FUNGI WHICH CAUSE PLANT DISEASE 



L. abietina (Bui.) Fr. occurs on firs. L. sepiaria (Wulf.) Fr. 

 has been reported as a parasite on pine, spruce, etc., but recent 

 work of Spaulding ^^ shows it to be merely a saprophyte. L. cor- 

 rugata Klot, L. vialis Pk. and L. betulina (L.) Fr. are common 



Fig. 312. — Daidalea quercina on oak. After von Schrcnk and Spaulding. 



saprophytes on deciduous trees; perhaps also parasitic; L. varie- 

 gata Fr. on beech and poplar. 



Boletaceae (p. 402) 



Sporophores fleshy, capitate, centrally or laterally stipitate, 

 rarely actually Siessile; hymenium on the under surface only, of 

 tubes which separate readily from the pileus and are united to 

 each other or only closely approximated. 



A family of less than three hundred species. 



Key to Genera of Boletaceae 



Pores adnate to each other I. Boletineae. 



Pores separate tubes II. Fistulineae. 



Sporophore more or less fleshy I. FistiUina, p. 441. 



Sporophore leathery 



Tubes with a central papilla 2. Theleporus. 



Tubes without pai)ill30 3. Porothelium. 



