44 A Monograph of the Myxogastres. 



black ; spores globose, 16 18 p. diameter ; epispore blackish 

 violet, smooth. 



Protoderma pusilla, Host., Mon., p. 90. 



Protodermium pusillum, Sacc., Syll., Vol. vii., pt. I, n. 1139. 



On rotten wood. Germany ; Russia ; United States. 



(Rostafinski's Synonyms.) 



Licea pusilla, Sclirad., Nov. Gen., p. 19, t. vi., f. 4 (1797). 

 Physarum licea, Fr., S. M., iii., p. 143 (1829). 



Sub-sect. ' CRIBRARIAE. 



ENTERIDIUM, Rost. (emended). 



Aethalium covered with a general, irregularly perforated, 

 membranaceous cortex ; walls of component sporangia with 

 symmetrical perforations, or irregularly broken up to form a 

 capillitium-like structure. 



Rost., Mon., p. 226; Cooke, Myx. Brit., p. 56; Schroeter, 

 p. 103 ; Sacc., Syll., Vol. vii., pt. I., p. 409. 



Very closely allied to the Clathroptychium, which differs 

 chiefly in the more complete absorption of the walls of the 

 sporangia. 



In E. olivaceum, which most nearly approaches Clathropty- 

 chium in structure, the side walls of the sporangia are not so 

 completely absorbed as in the last-named genus, hence the 

 thickened angles formed by the walls of contiguous cells have 

 broader and more irregular wings. 



Distrib. Europe ; United States ; W. Australia : species 3. 



A. Spores Reticulated. 

 Enteridium olivaceum, Rost. (f. 14 18). 



Aethalium very variable in form, flattened or pulvinate, olive ; 

 general cortex papery, pellucid ; walls of the crowded sporangia 

 pellucid, yellowish-brown, perforated; mass of spores olive; 

 spores in clusters of from 5 20, single ^orcs truncate, the free 

 portion convex and warted, remaining portion smooth, 11 15 p 

 diameter. 



