110 ENDOSPOREyE. [STEMONITIS. 



B. Spores pale ferruginous :- 



Spores 7 to 9 //, diam., plasmodium yellow. 



4. S. ferrugima. 



Spores 4 to 6 /A diain., plasmodium white. 



5. S. /Smithii. 



1. S. fusca Roth, in Rom. & Ust. Mag. Bot., i., pt. 2, p. 26 

 (1787). Plasmodium white, in rotten wood, maturing at the place of 

 emergence. Total height, 2 to 5 mm. Sporangia cylindrical, obtuse, 

 stipitate, purplish-black, at first closely fasciculate. Stalk black, 

 shining, 1 to 4 mm. long, O3 to 0'7 mm. thick, rising from a well- 

 developed, brown, membranous hypothallus. Columella reaching 

 to near the apex of the sporangium. Capillitium of dark brown 

 threads springing from all parts of the columella, combined into 

 a loose network, the ultimate branches forming a delicate super- 

 ficial net, with angular, unequal meshes varying from 6 to 16 p. 

 wide. Spores grey or rufous-violet, spinulose, with more or less 

 reticulated sculpture, 6 to 10 /x diam. Host., Mon., p. 193 ; Cooke, 

 Myx. Brit., p. 46; Blytt, Bidr. K. Norg., Sop. iii. (1892), p. 8; 

 Mass., Mon., p. 72 ; Macbride, in Bull. Nat. Hist. Iowa, ii., 

 p. 141. S. maxima Schweinitz, in Trans. Am. Phil. Soc. (1834), 

 p. 260 ; Macbride, I.e., p. 141. S. dictyospora Host., Mon., p. 195; 

 Mass., Mon., p. 83. S. nigrescens Rex, in Proc. Acad. Nat. Soc. 

 Phil. (1891), p. 392. S. Gastillensis Macbride, I.e., ii., p. 381, 

 Plate X., fig. 5. Amaurochcete speciosa Zukal, Verb.. Zool.-Bot. 

 Gesell. Wien, xxxv., p. 335, t. 15, f. 8. 



a. genuina : spores grey or violet-grey, reticulated, 8 to 10 //, 

 diam. 



p. rufescens : spores rufous-grey, faintly reticulated, 6 to 8 ^ 

 diam. 



y. confluens : sporangia confluent, lobed, without stalk, columella, 

 or superficial net. 



Plate XLIL, B. a., I. sporangia, a. genuina, x 2 ; c. capillitium, x 180 ; 

 d. sporangia (3. rufescens, x 2 ; e . capillitium, y. confluens, x 180; /. spore, 

 a. genuina, x 600 : g. spore, (3. rufescens, x 600 ; h. three spores from one 

 sporangium uniting the characters of a. and /3., x 600 (England) ; i. three 

 spores from one sporangium (England) ; It. spore of 8. trecMspora Berk., 

 x 600 (Venezuela). 



Plate LXXVIL, A. . pendulous aethalium, y. confluens, x 20 ; I. pul- 

 vinate sethalium, x 3 ; c. capillitium of same attached to a fragment of 

 sporangium-wall, x 180 ; d. spores, x 600 (Epping Forest, England). 



The spores of this very abundant species are never smooth, and 

 when magnified 1,200 diam. present the following modifications in 

 sculpture ; in a. this either consists of spines, thickened and connected 

 at their bases, forming a complete net with from 20 to 50 meshes on 

 the surface of the hemisphere, and giving a continuous border to the 

 spore; or the spines are less connected, forming a broken net, and 

 giving an irregular border to the spore ; or the spines are distinct, 

 arranged on a more or less reticulate plan, giving a spinulose margin 

 to the spore. In /3. the sculpture is usually less pronounced, but the 



