TJie Myxomycetes of the United States. 387 



20. Physarum obrusseum (B. andC). 



Didymium obrusseum B. and C, Cub., 532. 

 Didymium tenerrimum B. and C, Cub., 533. 



Spores -008— •01 mm . 

 Texas (Lindheimer) ; New Orleans (Drummond). 



21. Physarum simile Rost. 



Spores ■0075 mm . 

 Carolina (Curtis). 



22. Physarum elipsosporum Rost. 

 Enteridium olivaceum Schw., Am. Fung., 23G5. 

 Carolina (Schw.). 



23. Physarum schweinitzii, Berk., in Grevillea, N. A. Fungi, No. 358. 

 Polyangium vitellinum Schw., Am. Bor. 

 On vegetable fragments. Bethlehem (Schwz.). 



SPECIES UNCERTAIN". 

 24. Physarum elegans Schw., Am. Bor., No. 2294. ™ 



On leaves and plants. Salem (Schw.) ; Car. (Curt.). 



25. Physarum muscicola Schw., Am. Bor., No. 2278. 

 New York (Torrey). 



26. Physarum polycedron Schw., Am. Bor., 2300. 

 On old trunks of Juglans. Bethlehem (Schw.). 



27. Physarum ccespitosum Schw., Am. Bor., No. 2301. 

 On leaves and stems of Bhododendron. Bethlehem (Schw.). 



[Physarum cozspitosum Peck, from the color of the spores, 

 cannot be a Physarum; it may be the species of Schwcinitz, 

 for aught we can tell.] 



28. Physahum atrum Schw., Am. Bor., 2299. 

 On bark. Bethlehem (Schw.). 



Whatever Schweinitz's species may be, it does not appear 

 that Rostatinski considers the Physarum atrum of Fries to 

 be a Myxogaster at all. 

 Juke, 1877. 29 Ann. Lyc. Nat. Hist., Vol. xi. 



