STATE HORTICULTURAL SOCIETY 



9. P. diderma, Rostafinski. 

 Not common. 



10. P. context um, Persoon. 



Occurs on bark of fallen twigs, straw or grass stems, 

 lying undisturbed upon the ground. 



11. P. virescens, Ditmar. 



On moss or dead leaves lying on the ground. 



12. P. cinereum, (Barsch) Pers. 



Occurs in rich meadows, lawns or open prairie ; common. 



13. P. thejoteum, Fries. 



On rotten oak or fragments of charred logs. 



14. P. ccespitosum, Schweinitz. 



Rare, on mosses and rotting leaves. 



15. P. auriscalpium, Cooke. 

 On bark of fallen populus. 



16. P. variabile, Rex. 



17. P. didermoides, (Acharius) Rost. 



On fallen cottonwood or box-elder bark ; not common. 



18. P. nefroideum, Rostafinski. 

 Common. 



19. P. globidiferum, (Bull.) Pers. 

 Rare. 



20. P. leucopus, Link. 



On rails and stumps; rare. 



21. P. ravenelii, (Berk, and Curt.) Mass. 

 Not rare. 



22. P. pulclierrimum, Berkeley and Ravensel. 

 Not rare. 



23. P. galbeum, Wingate. 



A delicate plant, with hollow stipe. 



24. P. fiavicomum, Berkeley. 



On decayed elm logs; not common. 



25. P. penetrate, Rex. 



Readily recognizable by the elongate sporangia and 

 lengthened columella unique among Physarums. 



