OF GREAT BRITAIN. 37 



VI. PYRENIDIUM. Nyl. 



Thallus minute, stellato-divided or ceespitellose or confluendo- 

 effuse, of the same structure as that of Leptogium. Apothecia 

 pyrenocarpous verrucarioid. 



1. P. actinellum, Nyl. dark olivaceous, adnate, forming small 

 patches, stellato-divided, rays distinct, attenuated at their apices, 

 ascending or suberect, vinous-red with iodine ; apothecia pyreno- 

 deous, in the centre of the thallus, prominent, perithecium entirely 

 black; spores 4, fuscous or fuscescent, oblong, 3-septate ; paraphyses 

 few, slender or obsolete. 



On chalk, very rare. 1865. 



Stn :-NyI. in Flora 1865. p. 210. 

 Bot. Prov:— 3... 5. 



England : — Boxley Hill, Kent. Aim. Jones. (1865). Dorking. Mr. Joshua. 

 Crombie 1. c. states that," According to Nylanderim lift., if the apothecia 

 are not parasitic, this ought to be included in a distinct tribe called Pyrewidii." 



Fam : III. MYRIANGIACEI. 

 Tribe I. Myriangiei. 



I. MYRIANGIUM. Mnt & Berk 



Thallus black, noduloso-pulvinate, cellulose, uustratified. Apo 

 thecia sublecanorine, sphseroideo-cellulose. Spores 8, colourless; 

 oblong, irregularly septate, or almost murali-divided. 



1. M. Duriaei, M. <fc B. black, opake, small, tuberculato-glomerate 

 or noduloso-confluent, often depresso-pulvinate ; apothecia minute, 

 black, slightly impressed ; spores 8, colourless, oblong or oblongo- 

 ovoid, variously septate ; gelatina hymenea vinous with iodine. 



On ash and elm, rare. 1836. 



Syn :— Mnt. and Berk, in Hook. Journ. Bot. 1845, p. 73. Nyl. Syn. 139. 

 Gollema glomerulomrn, Tayl. Fl. Hib. 2. 108. excl. syn, 



Fig :— Nyl. Syn. t, 4. f. 1, 5. 



Exs:— Mass. 37. 



Geog. Distbib : — Europe, France, Algeria, Mexico, Australia, N. America. 



Bot. Prov :— 1, 2...19...31. 



England :— Penzance. Mr. Rolfs. Isle of Wight. Rev. T. Salwey. near Shank- 

 lin. Dr Holl. Trevello Wood, Cornwall. Mr. Gumow. 



Ireland : — Carrigaline ! near Cork ; near Crosshaven, Cork. Mr. Can-oil. 

 Roughty, Kerry. Dr. Taiilor. (1836). 



Channel Islands :— Sark ! Rev. T. Salwey. 



Fam : IV. LICHENAOEI. 



Thallus various in colour, white, whitish, cinerascent, flavicant, 

 rufous, fuscous, and very rarely nigricant, and very various in fornl, 

 filamentous, foliaceous, squamose, crustaceous, pulverulent or 

 evanescent. In most species the stratum gonidiale formed of true 

 gonidia, in a few only of granula gonima. Apothecia either 

 stipitate or lecanorine or peltate, or patellulate, or pyrenocarpous. 



Series I. Epiconiodei. 



Apothecia with the spores naked, collected into a sporal mass 

 on the surface. Spores 8, in asci. 



