PHYSARUM 65 



part below, all falls away, leaving the capillitium apparently intact, 

 crowded with spores. 



Canada south to Mexico; apparently, in one form or another, cos- 

 mopolitan. 



Var. confluens Brandza, Bull. Soc. Myc. Fr. 44 : 255, 1929, has ses- 

 sile or plasmodiocarpous, densely aggregated sporangia. 



34. Physarum murinum List. 



Mycetozoa 41. 1894. 

 PI. V, Figs. 79, 80. 



1891. Physarum braunianum Lister, Jour. Bot. 29 : 259, non Rost. 



1896. Cytidium ravenelii (B. & C.) Morgan, Jour. Cin. Soc. Nat. Hist. 19 : 10. 

 1899. Physarum ravenelii (B. & C.) Massee ex Macbr., N. A. Slime-Moulds 48. 

 1923. Physarum heterosporum Widder, Verb.. Zool.-Bot. Ges. Wien 73 : 159. 



Sporangia scattered, globose or perfectly spherical, ashy brown, 

 rugulose, stipitate; stipe elongate, pale brown, erect, generally taper- 

 ing upward, calcareous, brittle; hypothallus none; columella short, 

 hemispherical or bluntly conical; capillitium dense, much as in P. globu- 

 liferum, the calcareous nodules umber, brownish or orange-yellow, 

 small; spore-mass brown; spores by transmitted light bright lilac, 

 finely warted, the warts somewhat clustered, 8-11 ix. 



A very distinct species, easily known by its peculiar drab colored 

 peridium and dull brown stalks. The author of the species allows for 

 the capillitial nodes no other tint but brown. Under direct illumination 

 many gatherings, especially where the sporangia are well blown out, 

 show nodules of a bright orange tint. 



Morgan regarded his Cytidium ravenelii as the same as Berkeley 

 and Curtis' Didymium ravenelii. Lister, however, finds that the type 

 of the latter species is referable to P. pulcherripes Pk. Morgan's de- 

 scription seems to refer to the present species rather than to pulcher- 

 ripes and his name is therefore retained in the synonymy. 



Not rare in the eastern United States, to Missouri and Iowa, also 

 Washington; western Europe. 



35. Physarum melleum (Berk. & Br.) Massee 



Mon. 278. 1892. 

 PI. IV, Figs. 68, 69, 70, 71. 

 1873. Didymium melleum Berk. & Br., Jour. Linn. Soc. 14 : 83. 

 1873. Didymium chrysopeplum Berk & Curt., Grev. 2 : 53. 

 1876. Physarum schumacheri Spreng. var. melleum Rost., Mon. App. 7. 



1892. Physarum kalchbrenneri Massee, Mon. 297. 



1896. Cytidium melleum (Berk. & Br.) Morgan, Jour. Cin. Soc. Nat. Hist. 19:11. 



Sporangia scattered, stipitate, globose, somewhat flattened below, 

 0.4-0.5 mm. in diameter, wall rugose, clear yellow or honey colored; 



