The My.vomycctes of the Miami Valley, Ohio. 17 



Order W. ARCYRIACE.^. 



Sporangia regular and stipitatc, rarely sessile ; the 

 wall a thin membrane, minutely granulose, colored 

 as the spores and capillitium, the upper part soon 

 torn away in a somewhat circumscissile manner, and 

 early disappearing. Capillitium of slender tubules, 

 repeatedly branching and anastomosing to form a 

 complicated network of evident meshes, more or less 

 expanded after dehiscence ; the surface of the threads 

 minutely warted or spinulose or with elevated ridges 

 in the shape of rings, half rings or reticulations. 



This order is specially distinguished by the threads of the 

 capillitium forming a complicated network of evident meshes. 



TABI.E OF Genera of Arcyriace^. 



r. Lachnobolus. Capillitium of slender tubules, quite 

 variable in thickness, proceeding from numerous points of the 

 sporangial wall. 



2. Arcvria. Capillitium of slender tubules, issuing from 

 the interior of the stipe, the network without any free ex- 

 tremities. 



3. Heterotrichia. Capillitium issuing from the interior 

 of the stipe, the peripheral portion of the network bearing 

 numerous short acute free branches. 



I. LACHNOBOLUS, Fr. Sporangia .stipitate or sessile, 

 the wall a thin delicate membrane, minutely granulose, rup- 

 turing irregularly. Stipe short or sometimes wanting. Capilli- 

 tium of slender tubules quite variable in thickness, proceeding 

 from numerous points of the sporangial wall and forming a 

 complicated network, the .surface minutely warted or spinu- 

 lose. Spores globose, yellowish or flesh-color. 



