2l6 



OPEN TYPE OF ASCOCARPS 



cambium and cortical regions of the branches, causing the bark 

 to split open in the spring when spore bearing hyphae extend 

 up into the air forming velvety coating (Fig. 150, c). By the 

 approach of winter, this mycelium has grown into the familiar 

 black knotty mass in which are developed numerous ascocarp- 

 like bodies (Fig. 150, as). The spores from these ascocarps are 

 carried by the wind in the early spring to other branches and 

 probably infect the budding trees. Other conspicuous forms are 

 Xylaria and Daldinia, which develop an extensive stroma on 

 stumps and trees that contains numerous ascocarps (Fig. 152). 



Fig. 152. Other common forms of the Spheriales : A, habit of Hysterio- 

 graphium on a dead twig. B, ascocarps enlarged. C, ascus enlarged, 

 showing character of ascospores. D, Daldinia. E, section of the same, 

 showing that the stroma forms a concentric stratum of ascocarps, as. each 

 year. F, Xylaria. G, the same with branch cut off to show the layer of 

 ascocarps on the periphery of the stroma. 



In Hypoxylon, the stroma containing the ascocarps breaks through 

 the bark of a large variety of trees and shrubs in the form of 

 spherical or cake-like masses (Fig. 149)- 



89. Order f. Hypocreales. — These fungi are distinguished 

 from the Sphaeriales by their rather fleshy or membranous as- 

 cocarps and stroma, which range in color from white to yellow, 



