io Cincinnati Society of Natural History. 



pulchripes Peck, and Physarum petersii B. & C, mostly 

 belong here. The bright orange colors become dull or tawny 

 with age and exposure to the weather. 



4. Cytidium ravknki.ii B. & C. Sporangium globose, 

 stipitate; the wall a thin pellucid membrane, covered with 

 small scales of lime, from gray or drab to pale umber in 

 color, breaking up at maturity and falling away. Stipe 

 variable in length, concolorous with the sporangium or darker 

 below, tapering upward and entering the sporangium as a 

 short obtusely conical columella. Capillitium of tubules, 

 forming a dense net-work of very small meshes, with slight 

 expansions at the angles; the lime-nodules small, numerous, 

 ellipsoidal or obtusely angular, gray or drab to pale umber in 

 color. Spores globose, nearly even, pale violaceous, 7-9 mic. 

 in diameter. 



Growing on old wood, mosses, etc. Sporangium about .5 

 mm. in diameter, the stipe once to twice this length. The 

 species as here described includes Didymium ravenelii B. & 

 C, Physarum simile Rost., and Physarum ynurinum leister. 



5. Cytidium globulifkrum Bull. Sporangium globose, 

 the base sometimes flattened or slightly umbilicate, stipitate ; 

 the wall a thin, pellucid membrane, covered with small scales 

 of lime, white, cream-colored, or sometimes pinkish, breaking 

 up and falling away at maturity. Stipe variable in length, 

 white or smoky-white, usually darker below, rising from a 

 thin hypothallus, tapering upward and entering the sporan- 

 gium as a short obtuse or conical columella. Capillitium of 

 slender tubules, forming a dense, persistent net-work of very 

 small meshes, more or less expanded at the angles ; the 

 nodules of lime variable in size, numerous, white, roundish, 

 ellipsoidal or obtusely angular. Spores globose, nearly even, 

 pale violaceous, 7-9 mic. in diameter. 



Growing on old wood, bark, mosses, etc. A very common 

 and abundant species. Sporangium .5-6 mm. in diameter, 

 the stipe from once to two or three times this length. The 

 lime nodules in the capillitium are sometimes round and quite 

 minute, then again they are large and obtusely angular; the 

 columella varies from very short and conical to longer and 

 more cylindric. Diderma globuliferum of Fries S. M., 



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