14 ACOTYLEDONS. PUNGl. Uveclo. 



/S. vulgaris, crowded headsveryminute blackish. Miicor Mucedo, 

 Linn.; Hopk. Glott. p. 165 ; Sow. t. 378./. 5^ 6, and 7. 



Hab. On putrid wood^ bread^ and vegetables, at all seasons of the 

 year. Hopk. 



2. M.? Embolus, " stem black bristle-shaped set with brown 

 woolly hair." IVilh. Bot. Air. ed. 4. v. 4. p. 395. 



Hab. Found on rotten wood at all seasons, Hopk. 



19. iECIDIUM. 



Peridia (steniless) manifest, rounded, membranaceous, at length 

 opening with a dentated orifice. Sporules farinaceous, naked. 

 {Par aside on leaves.) 



Caespitose. Peridia crowded together so as to form a crustaceous sjwt 

 vpon the leaves. 



1. /E. cor nut urn, yellowish peridia very long curved olivaceous 

 grey. Pers. p. 205. Sow. t. 319. 



Hab. On the leaves of Sorhus Aucuparia, at Rosslyn, Slateford, Scc. 



August. Mr. GreviUe. 

 A singular plant, growing on the under side of the leaves, but forming 



a yellow spot in the upper. 



2. M. Tussilaginis, forming a purplish yellow spot, peridia 

 immersed nearly plane on their surface. Pers. p. 209. Sow, 

 t. ^^1 . f. 1. Lycoperdon epiphyllum, Hopk. Glott. p. 164. 



Hab. On the back of the leaves of Tassilago Farfura, very common, 

 Hopk. Mr. Greville. 



3. M. Berheridis, caespitose orbicular small convex, peridia 

 somewhat elongated yellow. Pers. p. 209. Sow. t. 397./. 5. 



Hab. On the leaves of Berheris vulgaris. This has been frequently 

 supposed to be the origin of the blight in wheat, but I suspect from 

 a common idea that the two plants are the same species. 



20. UREDO. 



Perjdium none. Dust naked, easily dispersed. Spcrules uni- 

 form, generally globose. 



* Dust yellowish {Rubigo, or Rust). - 



1. U. Alchemillce, crowded yellow and bursting the epidermis in 

 somewhat parallel lines. Pers. p. 215. 



Hab. Upon the leaves of Alchemilla vulgaris. Sept. Mr. Greville. 



Mr. Greville observes that his specimens differ somewhat from the de- 

 scription of Persoon. The sporules are brown, and the leaves upon 

 which they grow are not smaller than the rest ; contrary to the 

 observation of that author. 



2. U. Euphorbice Helioscopice, scattered somewhat globose pro- 

 minent yellow. Pers. p. 2\5. 



Hab. On the leaves of Euphorbia Helioscopia , at Arlary and Kinross. 



September. Mr. Greville. 

 3 U. ?nmjaf (7, roundish effuse orange-colour. Pen. p. 216, 



