156 Natural History Bulletin. 



Capillitium delicate, with rather small, irregular, yellowish,, 

 calcareous nodes. Columella none. Spores bright-violet,, 

 smooth, .0075-.009. 



This beautiful species occurs more commonly on moss- 

 tufts, with which it is frequently concolorous, or escaped upon 

 dead leaves, etc. The peridium is flecked with calcareous 

 scales or grains stained with yellow or green and to these 

 the whole fruit owes its peculiar color. The color and 

 aggregated, heaped sporangia are distinctive macroscopic 

 characters. 



58. Physarum LEUCOPH^UJM, Ffies. Plate IX, Figs. 2, 2a 



and 2b. 



Sporangia stipitate or sessile, depressed, spherical, ashy- 

 white bordering upon blue; stipes straight, anon connected, 

 variable, brownish. Columella none. Capillitium delicate 

 with numerous nodes, few calcareously thickened. Spores 

 smooth, dull violet, .008-.009. 



An exceedingly variable species; hard to identify from des- 

 cription merely. In Iowa a richly calcareous phase prevails,, 

 returning in plentiful abundance year by year. Sessile and 

 irregular sporangia predominate, but the same plasmodium 

 often yields sessile and stipitate, intergrading. The stipe 

 when present is more often white than brown, and the spores 

 are not smooth, but when highly magnified show the surface 

 covered with minutest points. Habitat, on fallen trees of vari- 

 ous sorts, chiefly and always to be found on the dead stems 

 of Pofidns grandidentata., Mx. September — December. 



59. Physarum leucopus, Link, Plate IX, Figs. 7, 7« 



and 73. 



Sporangia spherical, ovoid or depressed, stipitate, cinereous. 

 Stipe snow-white, occasionally borne upon a common hypo- 

 thallus, of varying lengths, tapering upward, stiff, brittle, with 



