LAMPRODERMA 



141 



the surface to form a slight delicate network with abundant 

 free ends; spores dark purple brown, rough, 1416 /u.. 



This species in outward appearance resembles L. pJiysaroides, 

 from which it is easily distinguished by the much greater 

 diameter of the globose sporangium, i mm. or more. The per- 

 sistent base of the peridium is also characteristic, very prom- 

 inent sometimes, and visible to the naked eye. The capillitium 

 is also unlike that of L. pliysaroides ; resembles more nearly 

 that of L. violaceum. From the latter species L. sautcri is 

 distinguished by the color of the peridium, and by the larger, 

 darker spores and generally different capillitium. This is 

 L. rolnista as distributed in the United States, but Mr. Lister 

 is certain that it is identical with the Rostafinskian form. L. 

 arcyrioides of Morgan's list appears to be the same. L. (5.) 

 arcyrioides Somm. apparently does not occur in this country. 



Washington. Ohio. 



3. LAMPRODERMA COLUMBINUM (Pers.} Rest. 



1796. Physarum columbinnm Pers., Obs. Myc., L, p. 5. 

 1875. Lamproderma columbinum Rost., Mon., p. 203. 



Sporangia scattered, gregarious ; rich violet or purple with 

 metallic iridescence, globose, stipitate ; the stipe long, three- 

 fourths the total height, slender, subulate, black ; hypothallus 

 scant, purplish or brown ; columella small, one-third the height 

 or less, tapering or acute, black ; the capillitium brown through- 

 out, not dense, arising from nearly all parts of the columella, 

 freely branching and anastomosing to an open, large-meshed 

 network ; spore-mass black, spores by transmitted light dark 

 brown, rough, 10-12 p. 



Rostafinski distinguished this beautiful species by the color of 

 the peridium and the conic columella. According to Mr. Lister, 

 Rostafinski was not specially careful in labelling his material, 

 different forms having been included under this specific name. 

 Nevertheless, the description is well drawn, and excludes L. 

 pJiysaroides completely. At all events our American specimens 

 correspond so well with the description of L. columbinum (Pers.) 



