PHY S ARUM 99 



A very handsome and rather common little species; like the pre- 

 ceding, but generally greenish-yellow '\n color, and occasionally bril- 

 liantly orange without a suggestion of green. Indeed, the color is so 

 variable that some authors have been disposed to discard the species 

 entirely, inasmuch as the chief specific character is color. The Plas- 

 modium is pale yellow, in rotten logs, stumps, etc. In the paler 

 yellow or greenish forms the stipe is more commonly black. 



This is Physaru?n luteurn (Bull.) Fries, and likewise also includes 

 the three varieties, viride, aiireum, coccineum, listed by the same 

 author under P. nutans, while he at the same time remarks that they 

 might with equal propriety be elsewhere referred. Rostafinski con- 

 siders that all the colored forms agree in capillitium sufficiently to be 

 associated under one name and are in the same way unlike T. 

 nutans.^ Rostafinski thinks to avoid confusion by suggesting a more 

 fitting specific name, T. mutabilis, but there seems no good reason for 

 not adopting the earliest identifiable specific appellation, which in this 

 case appears to be viride. The yellow phase is common in Iowa, 

 resembles in size, color, stipe, P. galheum Wingate, but is instantly 

 distinguishable by the capillitium. 'N . A. F., 1213. 



Widely distributed specimens are before us ; — from New England, 

 New York, Pennsylvania, Maryland, Ohio, Nebraska, Iowa, Cali- 

 fornia, Oregon, Canada, Nicaragua, Samoa, Alaska, India, etc. 



EXTRA.LIMITAL2 



Physarum mutabile (Rost.) List. 



1875. Crateriachea mutabilis Rost., Mon., p. 125. 



1892. Crateriachea mutabilis Rost., Mass., Mon., p. 344. 



1894. Physarum cinereum List, Mycetozoa, p. 55, in part. 



1895. Physarum crateriachea List., Jour. Bot. XXXIIL, p. 323. 



1910. Physarum crateriachea List., Fetch, Mycetozoa Ceylon, p. 336. 



1911. Physarum mutabile List., Mycetozoa, 2nd ed., p. 53. 



Sporangia cylindrical ovoid or subglobose white, plasmodiocarpous, 

 sessile or stipitate, stipes when present yellow, with or without lime, 

 often connected by a hypothallus ; peridium thin, squamulose ; capil- 



1 The Polish author wrote Tilmadoche instead of Physarum in each case 

 cited. 



- Forms cited are chiefly those likely to be found in our neighboring tropics, 

 West Indies, etc. 



