}66 LICHENES. [Spiluma. 



frequently almost covering the thallus. Sporules so minute that the 

 highest powers of the microscope are insufficient to discover their figure ; 

 those of the surface, which are deep brown with a fuliginous tinge, 

 rub off with the slightest touch and discover the dull but full yellow (or 

 orange-) colour of those which compose the internal part of the apo- 

 thecium."— In E. Bot., S. auratum is described and figured with a crust, 

 not belonging to it ; for it often spreads over the thick tartareous thalli 

 of Verrucaria and Opegrapha, &c. 



6. S. nigrum. Turn, and Borr. (black Spiloma); crust inclin- 

 ing to tartareous thin white with a narrow black edge, apothe- 

 cia roundish nearly flat at length confluent black. Turn, and 

 Borr. Lick. Br. p. 35. — cc. variolosum ; crust powdery pure 

 white, apothecia convex but little confluent black. Coniocarpum 

 nigrum, Be Cand. Fl. Fr. ed. 2. v. 2. p. 324. Bubis and Be 



Cand. Bot. Gall. v. 2. p. 695 Spiloma variolosum, E. Bot. 



t. 2077. — S. melaleucum, Ach. Syn. p. 2. — (3. versicolor; crust 

 inclining to powdery grey variegated with greenish-yellow, 

 apothecia flat very confluent. *S y . versicolor, Ach. in Web. et 

 Mohr Arch. p. 108. E. Bot. t. 2076. — y. erubescens; crust tar- 

 tareous reddish cracked into areolae, apothecia small shapeless 

 for the most part distinct. 



Not unfrequent on old trees, chiefly Oaks; sometimes on bare wood 

 in sheltered places. Old Church-walls in Suffolk. Sir T. Gage, Bart. — 

 /3. On smooth bark, as on Hornbeam, in Norfolk and Suffolk, and on 

 Walnut at Albourne, Sussex. — y. on smooth trees in Norfolk and Suf- 

 folk, and at Henfield and Albourne, Sussex. 



7. S. fuliginosiun, Turn, and Borr. {sooty-fruited Spiloma); 

 crust inclining to tartareous but still very thin nearly white with 

 a fuliginous edge composed of downy fibres, apothecia very 

 minute punctiform * confluent sooty-black. Turn, and Borr. 

 Lick. Br. p. 37. — S. microclonium, E. Bot. t. 2150, {not Ach.). 



On the rugged trunks of old trees. In Windsor forest, Mr. Sowerby. 

 Near Esher, Surrey ; Belton and Blundeston, Suffolk. — Allied to S. 

 nigrum, from which it is distinguished by the colour, size and indistinct 

 figure of its innumerable apothecia, which are so uninterruptedly scat- 

 tered over the thallus as to render the plant liable to be mistaken for a 

 Lepraria. 



8. S. decolorans, Turn, and Borr. (staining . Spiloma); crust 

 spreading widely very thin and for the most part filmy, apothe- 

 cia flat inconspicuous confluent of a purplish- grey. Turn, and 

 Borr. Lich. Br. p. 39. E. Bot t. 2399. 



Common on old walls, boarded buildings and pales. — This is, in habit, 

 allied to some Variolarice; but as the fructifications appear to be pulvi- 

 nuli rather than soredia, the plant is arranged here. 



9. S. punctatum, Turn, and Borr. (dotted Spiloma); crust 

 filmy somewhat powdery thin white, apothecia scattered mi- 

 nute punctiform solid, sporules blackish-brown superficial. 

 Turn, and Borr. Lich. Br. p. 40. E. Bot. t. 2472. 



On old oaks at Coltishall, Norfolk.— Of doubtful genus, in some re- 

 spects allied to Arthonia, in others to S. gregarium. 



