LAMPRODERMA 139 



deciduous, except where, at the base of the columella, it forms 

 a ring around the stipe ; capillitium rising in tufts or by simple 

 branches from the columella, the threads regularly forked, gen- 

 erally united into a net. 



The Lamprodermas are distinguished from the Comatrichas, 

 to which they are most nearly allied, by the arrangement of the 

 capillitium, its development from the apex only of the columella, 

 the continuation of the stipe within the peridium. In other 

 words, the peridium leaves the stipe some distance below the 

 point where the lowest capillitial branches take origin. In 

 mature specimens the peridium has often entirely disappeared, 

 its only trace, a collar, more or less distinct, around the stipe, 

 marking the beginning of the columella. Nevertheless the 

 peridium is far more persistent than in any Comatricha, and 

 shows in yet greater brilliancy the wondrous metallic tints and 

 iridescence of Comatricha and DiacJiea. Older authors, so far 

 as can be seen, distributed the species between PJiysanim and 



Stemonitis. 



Key to the Species of Lamproderma. 



A. Peridium metallic blue. 



a. Stipe short, stout. 



i . Capillitium tips colorless . . 5. L. violaceum 



b. Stipe long, slender. 



1 . Capillitium of dark, tapering, oft -united threads, 



3. L. cohonbinum 



2. Capillitial threads rigid, dark brown, seldom united, 



4. L. irideum 



B. Peridium not blue, silvery. 



a. Stipe long, slender. 



1 . Capillitium very intricate, forming a compact net, 



6. L. arcyrionema 



2. Capillitium of rigid dark brown threads . I. L. physaroides 



b. Stipe short, heads large, i mm. or more . . 2. L. santeri 



i. LAMPRODERMA PHYSAROIDES (Alb. and Sc/nv.} Rost. 



1805. Physarum physaroides Alb. and Schw., Consp. Fung., p. 103. 

 1875. Lamproderma physaroides (Alb. and Schw.) Rost., Man., p. 202. 



Sporangia gregarious, widespreading, globose, the peridium 

 persistent with a silver metallic, sometimes brassy, lustre ; stipe 



