162 A Monogmpli of the Myxogastrea. 



Arcyria melanopeziza, Mass. 



Sporangia sessile, creeping, suhierctc, generally forming rings, 

 1 — 2 mm. long, very Hack, scarcely or not at all shining, very 

 smooth; wall black, opaque, subcellular, rather coriaceous, 

 splitting longitudinally and deliiscing in a valvate manner; 

 capillitium yellow, protruded elastically, threads round, 4 — 5 ix 

 thick, combined into a loose net, everywhere covered with erect 

 spines, 5 — 6 x 1 /a, spirals almost obsolete ; spores elliptico-glohose, 

 pap)illoso-scalrid, 10 — 12 x 10 /x, yellow. 



Hemitriehia melanopeziza, Spegazzini, Fung. Arg., Pug. IV., 

 n. 268. 



Hemiarcyria melanopeziza, Berlese, Sacc, SylL, vii., 1, n. 1520 ; 

 Mass., Rev. Trich., p. 356. 



On bark. Brazil. 



Looking exactly like some black Peziza. 



Arcyria calyculata, Mass. 



Sporangia simple, gregarious, stipitate, globose or elliptical, 

 dirty foxy-brown, 1 — 2 mm. diameter; stem 3 — 5 mm. long, 

 200 — 250 /a thick, round, glabrous, rather tough, apex dilated 

 into a little dimidiate cup equal to the pcridium, base dilated, 

 fibrillose, colour of the sporangium ; spores and capillitium dingy 

 yellowish -fulvous; elaters 7 — 8 }x thick, cylindrical, yellowish, 

 sparsely branched, free tips acute ; spirals 3 — 5, flat, not very 

 conspicuous, separated by interspaces their own width, spinulose ; 

 spores discoideo-lenticular, concavo-convex, margin muriculate, 

 10 X 3 fA diameter. 



Hemiarcyria calyculata, Speg., Fung. Arg., Pug. III., n. 92 ; 

 Sacc, Syll, n. 1518; Mass., Revis. Trich., p. 356. 



On rotten willow trunk. Argentine Republic. 



It is very doubtful as to whether the spores in the normal 

 condition present the shape described by Spegazzini ; the 

 spores of many species become concavo-convex when dry, but if 

 soaked for a sufficient length of time, assume the usual spherical 

 form. 



