PHYSARUM 45 



membranous layer closely applied to the limy outer coat, not scaly, 

 but breaking irregularly; capillitium densely calcareous, the nodules 

 angular, branching, sometimes united to form a pseudocolumella; 

 spores dusky violaceous, rough, 9-12 jx. The plasmodium is said to 

 be white. 



Sommerfeldt's description, quoted by Fries, evidently concerned a 

 less calcareous phase. Fries by his annotation relieves somewhat the 

 reader's uncertainty. Rostafinski calls this a badhamia but describes 

 a physarum, and the form has frequently been confused with P. cine- 

 reum from the days of de Bary until now. In the second edition of the 

 Mycetozoa, Lister clears the situation by transferring the species to 

 Physarum, and calling attention to spore dimensions. From all con- 

 nection with Badhamia, as representing B. panicea, it should, as would 

 appear, be withdrawn once and for all. 



Mainly an old-world species. Many of the American collections so 

 referred are better regarded as forms of P. cinereum with large spores. 

 The European material in our collection is more definitely plasmodio- 

 carpous and seems to have a much firmer wall, even in the less cal- 

 careous forms referred to as var. iridescens Lister. Whether all large- 

 spored collections from America should be referred to P. cinereum 

 is doubtful, however. Our only American specimens were sent by 

 Mr. Hagelstein from Long Island. 



New York, Washington, Cuba; Europe, South Africa, Hawaii, 

 Australia. 



Var. iridescens G. Lister lacks the limy outer coat, and, in material 

 furnished by Miss Lister, is less plasmodiocarpous. Europe. 



3. Physarum cinereum (Batsch) Pers. 



Roemer N. Mag. Bot. 1 : 89. 1794. 

 PI. Ill, Figs. 45, 46. 



1786. Lycoperdon cinereum Batsch, Elench. Fung. Cont. 1. 249. 



1809. Physarum griseum Link, Mag. Ges. Nat. Fr. Berl. 3 : 27. 



1829. Didymium cinereum (Batsch) Fr., Syst. Myc. 3 : 126. 



1829. Physarum plumbeum Fr., Syst. Myc. 3 : 142. 



1845. Didymium scrobiculatum Berk., Hook. Lond. lour. Bot. 4 : 66. 



1875. Physarum cinereum (Batsch) Pers. ex Rost., Mon. 102, in part. 



1892. Physarum scrobiculatum (Berk.) Massee, Mon. 300. 



Sporangia sessile, closely gregarious or heaped, subglobose, elongate 

 or plasmodiocarpous, more or less calcareous, lilaceous gray; peridium 

 simple, thin, more or less densely coated with lime; capillitium strongly 

 developed, the internodes more or less richly calcareous and badhami- 

 oid, the lime-knots rounded and angular; spore-mass purplish brown, 



