DIACHEA 147 



c. Stalks equalling or exceeding height of sporangia d 



c. Stalks very short, sometimes lacking e 



d. Spores sparsely and irregularly warted 2. D. bulbillosa 



d. Spores with numerous dark warts and lines forming an im- 

 perfect reticulation 3. D. splendens 



e. Spores spinulose or warted 4. D. radiata 



e. Spores distinctly warted-reticulate 5. D. subsessilis 



f. Calcareous deposits orange or orange-yellow 6. D. thomasii 



f. Lime lacking; stem translucent, waxy or black, with wax 



deposited as a collar at junction with sporangium 7. D. cerifera 



1. DlACHEA LEUCOPODIA (Bull.) Rost. 



Mon. 190. 1875. 

 PL X, Figs. 226, 227, 228. 



1791. Trichia leucopodia Bull., Champ. 121, PI. 502, fig. 2. 



1797. Stemonitis elegans Trentep. in Roth, Cat. Bot. 1 : 220. 



1801. Stemonitis leucostyla Pers., Syn. Meth. Fung. 186. 



1805. Stemonitis leucopodia DC, Fl. Fr. 2 : 257. 



1825. Diachea elegans Fr., Syst. Orb. Veg. 143. 



1892. Diachea confusa Massee, Mon. 259. 



Sporangia rather closely gregarious, metallic blue or purple-irides- 

 cent, cylindric or ellipsoidal, obtuse, subumbilicate below, stipitate; 

 stipe short, much less than one-half the total height, snow-white, 

 tapering upward; hypothallus white, venulose, forming an open net- 

 work over the substratum from which the sporangia arise; columella 

 thick, cylindric, tapering, blunt, terminating below the apex, white; 

 capillitium springing from every part of the columella, of slender 

 threads, brown, flexuous, branching and anastomosing to form an 

 intricate net; spores in mass nearly black, by transmitted light dull 

 violaceous, minutely roughened, 8-11 ix. 



A very beautiful species; common in the United States. Easily 

 recognized, amid related forms, by its snow-white stem and cylindri- 

 cal sporangium. Fries adopted the specific name proposed by Trente- 

 pohl and wrote D. elegans, simply because to him the peridium was 

 "admodum elegans." 



The peridium is exceedingly thin and early deciduous; the stipe 

 long-persistent. The Plasmodium, dull white, was observed by Fries 

 at the beginning of the century; "morphoseos clavem inter myxo- 

 gastres hoc genus primum mihi subministravit." Rostafinski wrote 

 the specific name leucopoda, in which spelling he is followed by Massee 

 and Lister. Bulliard wrote leucopodia and there seems to be no reason 

 for changing the spelling. 



This species, as the diacheas generally, affects fallen sticks and 



