ARCYRIA 263 



or where they have been broken off, lobes and the lower calyculus 

 often darker than the rest of the peridium; inside of peridium marked 

 with warts which are sometimes elongated into ridges; capillitium in- 

 elastic, sometimes rather scanty, the threads 3-4 /x wide, warted, 

 ridged or rarely imperfectly ringed or spiralled, with inflations 7-25 n 

 across; spores very minutely spinulose, with a few scattered warts, 

 7-8 ix. Plasmodium white, then rosy. 



Miss Baskerville, who studied this species carefully, agrees with 

 Mr. Lister that its affinities are with Arcyria rather than with 

 Lachnobolus. 



Maine to Manitoba, south to Missouri and Nebraska. 



2. Arcyria Wiggers 

 Fl. Holsat. 109. 1780. 



Sporangia ovoid, cylindric or globose, stipitate or almost sessile; 

 peridium thin, evanescent to near the base, the lower part persisting 

 as a calyculus; stipe variable, often packed with free cell-like vesicles 

 resembling spores, but larger; capillitium an elastic network, the 

 tubules adorned with warts, spinules, half-rings or cogs, but without 

 spiral bands or free extremities, usually attached below, to the interior 

 of the stipe or to the calyculus. 



Micheli, of course, discovered the arcyrias, put them in two genera 

 and several species, which we may only dimly recognize. Persoon 

 first saw distinctly the outlines of the genus as now understood and 

 adopted the name given by Hill (Gen. Nat. Hist. 2 : 47) in his 

 curiously prolix description of certain species, probably partly of the 

 genus Arcyria, partly Stemonitis, and first used after 1753 by Wiggers. 



KEY TO THE SPECIES OF ARCYRIA 



a. Capillitium almost or quite free from the calyculus b 



a. Capillitium attached to the calyculus i 



b. Mature capillitium far expanded, drooping c 



b. Mature capillitium short, not drooping, though sometimes procumbent . / 



c. Sporangia dusky, with gray to reddish tints d 



c. Sporangia yellowish or greenish e 



d. Large, 6-12 mm., tawny gray, spores 7-8 n 1. A. magna 



d. Of medium size, 4-6 mm., dull crimson, sometimes 



vermilion, spores 8-10 ju 2. A. cerstedtii 



e. Pale yellow or buff; calyculus broad 3. A. nutans 



e. Yellowish green; calyculus narrow 4. A. virescens 



f. Obovate or pyriform; olivaceous with yellow and reddish 



tints 5. A . versicolor 



/. Oval or cylindrical; reddish or flesh colored, at length 



sordid & 



