266 E. A. Vainio, Lecideales. 



Affinis est Bilimbiae lignariae (Ach.) Arn. et B. chlorococcae, 

 ab ambabus bene differens. — Thallus interdum crustam sat 

 crassam formans, passim parce sorediosus. Perithecium ex hyphis 

 ramoso-connexis, pachydermaticis formatum, cavitatibus cellularum 

 oblongis, circ. O.ooos mm latis, chondroideum, subdecoloratum aut 

 pallidum. Hypothecium in parte superiore ex hyphis erectis for- 

 matum, limite subhymeniali baud distincto, KHO non reagens. 

 Hymenium circ. O.050 — O.ioo mm crassum, jodo caerulescens, dein 

 vinose rubens, ascis caeruleo-violascentibus. Paraphyses arete 

 cohaerentes, parce ramoso-connexae, tubulis O.0015 mm crassis, 

 membranis modice gelatinoso-incrassatis, in KHO turgescentibus, 

 septatae. Asci clavati. Sporae 8:nae, decolores, rectae aut 

 leviter curvatae flexuosaeve, apices versus tenuiores aut apici- 

 bus obtusis vel rotundatis, septis vulgo 1 — 3, raro 4 — 5 aut 

 simplices, long. O.015 — O.040, crass. 0. 005— 0. 007 mm. Gonidia 

 micareoidea, glomerulosa, cellulis subglobosis aut subellipsoideis, 

 diam. O.004 — O.005 mm, membrana modice incrassata, chromato- 

 phoro dilute flavescente. 



Sect. 2. Arthrospora (Mass.) Vain. 



Arthrosporam Mass. Mem. Lich. (1853) p. 127; Koerb. Syst. Lich. 

 Germ. (1855) p. 270. Arthrospora Th. Fr. Gen. Heterol. (1861) p. 88, 

 Lich. Scand. II (1874) p. 584. Bacidia sect. 1. Arthrosporam Zahlbr. 

 Ascol. (1905) p. 136. 



Sporae 8:nae — 16:nae. 



23. B. populorum (Mass.) Vain. 



Arthrosporam populorum Mass. Mem. Lich. (1853) p. 128, fig. 199. 

 Lecidea acclinis Flot. in Koerb. Syst. Lich. Germ. (1855) p. 270, Parerg. 

 Lich. 3 Lief. (1861) p. 242; Nyl. Lich. Paris (1896) p. 88. Arthrosporam 

 accline (Flot.) Mass. Geneac. Lich. (1854) p. 20; Koerb. Syst. Lich. 

 Germ. (1855) p. 270. Arthrospora acclinis Th. Fr. Gen. Heterol. (1861) 

 p. 88, Lich. Scand. II (1874) p. 585. Lecidea accline Nyl. Lich. Scand. 

 <1861) p. 219. 



Exs. Mass. Lich. Ital. Exs. VI (1856) n. 204. — Hepp Flecht. Eur. 

 II (1857) n. 281. — Rabenh. Lich. Eur. Exs. VIII (1857) n. 204. — 

 Fellm. Lich. Arct. (1864) n. 179. — Norrl. et Nyl. Herb. Lich. Fenn. VII 

 U882) n. 322 a-c. 



Thallus verruculoso-inaequalis, esorediatus. Apothecia 

 sat parva, basi late adnata, atra, disco piano aut demum 

 depresso-convexo, marg-ine tenui, subpersistente aut demum 



