110 ENDOStOEEiE. [STEMONITIS. 



B. Spores pale ferruginous : — 



Spores 7 to 9 /A diam., plasmodium yello-w, 



4. S. 



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



5. <S^. Smithii. 



1. S. fasca Eoth, in Rom. & Ust. Mag. Bot., i., pt. 2, p. 26 

 (1787). Plasmodium wliite, 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, 0'3 to 0'7 mm. thick, rising from a well- 

 developed, brown, membranous hypothallus. Columella reaching 

 to near the apex of the sporangium. Oapillitium 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 fi, 

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

 reticulated sculpture, 6 to 10 /a diam. — Rost., 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, Z.c.,p. 141. S. dictyospora Rost., 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. AmauroohoBte speciosa Zukal, Verh. Zool.-Bot, 

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



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

 diam. 



p. mfescens : spores rufous-grey, faintly reticulated, 6 to 8 /a 

 diam. 



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

 or superficial net. 



Plate XLII., B.-^a., b. sporangia, a. genuina, x 2 ; o. capillitium, x 180 ; 

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

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

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

 spores from one sporangium (England) ; Ii. spore of S. trechispora Berk., 

 X 600 (Venezuela). 



Plate LXXVII., A. — a. pendulous- sethalium, y. canfluens, x 20 ; J. pul- 

 vinate ffithalium, 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 60 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 fi. the sculpture is usually less pronounced, but the 



