TIBEISSEA. 319 



4. Vibrissea microscopica. B. and Br. 



Very minute, plane or cup-shaped; hymenium and 

 receptacle grey; stipes short, slender, black; asci clavate; 

 sporidia 8, filiform ; paraphyses filiform numerous. 



Vibrissea microscopica — B. and Br., " Ann. Nat. 

 Hist.," No. 1618 ; " Grevillea," v. p. 59 ; Phil, in " Trans. 

 Linn. Soc," ser. 2, vol. ii. p. 7, t. i. f. 17-24. 



On damp fir- wood. 



Scarcely visible without a lens. Stem very short, 

 black ; head grey, leaving a cup-shaped depression when 

 completely washed off; sporidia ejected, filiform (Berk, 

 and Broome, I. c). 



The receptacle is 200,u broad ; the whole plant 200/i 

 high ; sporidia 50 — 60 X 2/u. 



Name — iwcpog, small, (ncowiu), to look ; from its minute- 

 ness. 



Rannoch, NB. ! (Dr. Buchanan White). 



B. SESSILE. 



5. Vibrissea Guernisaci. Crouan. 



Minute, lentiform or turbinate, between fleshy and 

 gelatinous ; hymenium pallid, ochraceous or grey, convex ; 

 asci cylindrical, long ; sporidia 8, filiform, hyaline, 270/x 

 long; paraphyses slender, branched near the clavate 

 summits. (Plate X. fig. 61.) 



Vibrissea Guernisaci — Crouan, "Ann. Sc. Nat.," 

 1857, t. iv. f. 24-26 ; "Flo. Fin.," p. 46 ; Phil, and Plow., 

 "Grevillea," iv. p. 120; Phil., "Trans. Linn. Soc," ser. 2, 

 vol. ii. p. 8, t. ii. f. 1-7 ; Gill., " Champ.," p. 204, c. i. ; Pat., 

 p. 168, f. 369. 



Exs.— Phil., " Elv. Brit.," No. 143. 



On dead submerged branches of Salix in water. May 

 and June. 



Cups J to 1J lines broad. It first appears on the 

 branches as a small greyish wart, with a somewhat paler 

 point in the centre. In a more advanced state it assumes 

 the form of a thick disc, similar to the apothecia of 

 Lecanora. The hymenium is convex, soft in texture, 



