98 THE NORTH AMERICAN SLIME-MOULDS 



Persoon changed Bulliard's specific name in this case to furnish 

 one himself, more descriptive as he thought and distinctive. His suc- 

 cess in this attempt must be esteemed but partial since all the related 

 forms, immediately listed, nod as well. Bulliard's name as applied 

 by Persoon is therefore to be preferred. But the transfer from Til- 

 madoche to Physarum loses for us one step in the ladder of priority. 

 P. album (Bull.) may not enter here, since Fries has given us one 

 species under that title. So Persoon comes next on the list, all the 

 world now nodding approbation, let us hope! 



Under the name Physarum gracilentum, Fries cites an extremely 

 delicate form of this species. The sporangia are of the most minute, 

 about .2-3 mm. in diameter, globose, slightly umbilicate below, the 

 stipe usually white at top, but sometimes black throughout. This 

 graceful form occurs rarely in undisturbed woods. 



Widely distributed in the eastern United States, apparently rare 

 in the west. Reported from various parts of the world; Europe, 

 Japan, Australia, etc. 



56. Physarum viride (Bull.) Pers. 



• 1791. Sphaerocarpus viridis Bull., Champ., t. 407, Fig. I. 



1791. Sphaerocarpus luteus Bull., Champ., t. 407, Fig, II. 



1791. Sphaerocarpus aurantius Bull., Champ., t. 484, Fig. II. 



1791. Stemonitis viridis (Bull.) Gmel., Sys. Nat., p. 1469. 



1794. Physarum aureum Pers., Romer, Neu. Mag. f. die Bot., I., p. 88. 



1795. Physarum viride Pers., Usteri, Ann. Bot., XV., p. 6. 

 1801. Physarum aurantium Pers., Syn. Meth., p. 173. 



1829. Physarum nutans var. Fries, Syst. Myc, III,, pp. 128-129. 



1875. Tilmadoche mutahilis Rost,, Mon., p, 129. 



1880, Tilmadoche viridis (Bull.) Sacc, Michelia, II,, p. 263. 



1894. Physarum viride Pers., List., Mycetozoa, p. 50. 



1899. Tilmadoche viridis (Bull.) Sacc, Macbr,, N. A. S., p. 59. 



1911. Physarum viride Pers,, List,, Mycetozoa, 2nd ed. 



Sporangia globose, flattened or lenticular, beneath plane or con- 

 cave, variously colored, yellow, greenish yellow, rusty orange, stipi- 

 tate, nodding; the peridium splitting irregularly or reticulately ; 

 stipe variable in length and color, through various shades of red and 

 yellow, subulate ; capillitium strongly developed, concolorous with 

 sporangium, the tubes with colorless or yellow calcareous thicken- 

 ings; spores smooth, fuscous or violet-black, 8 fi. 



