DICTYDIUM 



171 



15. CRIBRARIA CUPREA Morgan. 



PLATE XVII., Fig. 7. 

 1893. Cribraria cuprea Morg.,Jour. Cm. Soc., p. 16. 



Sporangium very small, .33 mm., oval or somewhat obovoid, 

 copper-colored, stipitate, nodding; stipe concolorous or darker 

 below, subulate, curved at the apex, 2-4 times the sporangium ; 

 calyculus about one-half the sporangium, finely ribbed and 

 granulose within, the margin nearly even ; the net rather rudi- 

 mentary, the meshes large, triangular or quadrilateral, the 

 nodules also large, flat, concolorous, the threads slender, trans- 

 parent, with free ends few ; spores in mass copper-colored, by 

 transmitted light colorless, smooth, 6-7 p. 



Recognizable by its small size and peculiar color, that of 

 bright copper, although this fades somewhat with age, and the 

 metallic tints are then lacking. Related to the preceding and 

 in specimens having globular sporangia closely resembling it ; 

 but the ground color in C. languesccns is always darker, and the 

 stipe proportionally much longer. In habit the sporangia are 

 widely scattered, much more so than is common in the species 

 of this genus. 



Comparatively rare. Before us is one very small colony of 

 sporangia from Iowa, one from Ohio, and a large number from 

 Missouri. If one may judge from material at hand, the favorite 

 habitat is very rotten basswood, Tilia americana. 



2. Dictydium (Schmd.) Rost. 



Sporangia distinct, gregarious, globose or depressed-globose, 

 stipitate, cernuous ; the peridium very delicate, evanescent, 

 thickened on the inside by numerous meridional costae which 

 are joined at frequent intervals by fine transverse threads more 

 or less parallel to each other, forming a persistent network of 

 rectangular meshes. 



The ribs or costse of the spore-case radiate from the top of 

 the stipe and unite again at the top of the sporangium in a 

 feebly developed irregular net. Schrader, Nov. Gen. PL, p = 1 1, 



