The Myxomycetes of the Miami Valley, Ohio. 165 



23. Stemonitis. Threads of the capillitium forming an 

 interior network of large meshes and a superficial network of 

 smaller meshes. 



24. Enerthenema. Threads of the capillitium pendent 

 from a discoid membrane at the apex of the columella. 



B. Stipe and columella white or yellowish. 



25. Diachea. Threads of the capillitium branching and 

 anastomosing to form a network. 



§4. CALCARK^. 



On or within the walls of the sporangia and often in the 

 capillitium deposits of lime under the form of granules or 

 crystals of carbonate of lime. 



VIII. DIDYMIACE^E. Wall of the sporangium a thin 

 membrane with an outer layer of crystals or granules of 

 lime ; columella usually conspicuous ; capillitium of slender 

 sinuous threads, scarcely branched and containing no lime. 



a. Lime on the wall of the sporangium in the form of minute 

 stellate crystals. 



26. Didymium. Sporangium simple, subglobose, and 

 stipitate, the base commonly umbilicate, or sometimes sessile 

 and plasmodiocarp. 



27. Spumaria. Aethalium composed of numerous elon- 

 gated irregularly-branched sporangia closely compacted to- 

 gether and confluent. 



b. Lime on the wall of the sporangium consisting of minute 

 ro2inalish grantcles. 



28. Diderma. Wall of the sporangium with the outer 

 calcareous layer usually compacted into a smooth continuous 

 crust. 



29. IvEpidoderma. Wall of the sporangium with an outer 

 layer of large scales consisting of bicarbonate of lime. 



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