PHYSARUM 49 



none ; columella short, hemispherical or bluntly conical ; capil- 

 litium dense, much as in P. globuliferum, the calcareous nodules 

 not infrequent, yellow, small ; spore-mass brown ; spores by 

 transmitted light, bright lilac, almost smooth, 6.5-7.5 p. 



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

 colored sporangia, yellow capillitium, and singular fusiform 

 stem. In the persistence of the capillitium as a spherical mass 

 the species recalls P. globuliferum, but is after all quite unlike 

 that species. The peridium is sometimes iridescent above and 

 below, corresponding probably to the " metallic scales " of the 

 original description. Grevillea, 1873, p. 53. 



Lister's effort, I.e., to place this species under P. petersii or 

 P. pulcJiripes does not seem to us fortunate ; and his P. 

 murinum is certainly the same thing. 



Not rare. Massachusetts, New York, Ohio, Missouri, Iowa. 



28. PHYSARUM PULCHERRIMUM Berkeley and Ravenel. 



1873. Physarum pulcherrimum Berk, and Rav., Grev., II., p. 65. 

 1875. Physarum pulcherimum (Berk, and Rav.), Rost., Man., p. 105. 

 1879. Physarum atrorubrnm Peck, Rep. N. Y. Mus., XXXI., p. 40. 



Sporangia scattered or gregarious, globose, even or somewhat 

 wrinkled, dark red, stipitate ; stipe cylindric, even, sub-concolor- 

 ous or blackish ; columella small or none ; capillitium free from 

 spores, whitish, with a slight pinkish tinge ; spores dark brown 

 in mass, dark red when separated, globose, smooth, 7.5-8.5 /*. 



The capillitium is very delicate, and when cleared of spores 

 the knot-like thickenings are seen to be very small and of a 

 dark red color, to which is probably due the pinkish tinge which 

 marks the whole. A part only of the thickenings are filled with 

 lime granules. The dark red granules of the sporangium walls 

 are abundant and appear to form a continuous crust. 



This is P. atrorubrum Peck, and his description, I.e., has 

 been closely followed. The very brief description in Grevillea, 

 however, antedates the New York publication and, all inade- 

 quate as it is, no doubt applies to the same thing. 



Not rare. New York, Pennsylvania, Ohio, Missouri, Iowa. 



