OF GREAT BRITAIN, 9 



Fam. I. BYSSACEI. 



Thallus black or fuscous, filamentose, byssoid ; granula gonima 

 in 1-2 or 3 series enclosed in a vagina. 



Tribe I. SIROSIPHEI. 



Thallus minute, filamentose, densely implexed or compacted, 

 vaginate, granula gonima in 1-2-3 series. 



I. SIROSIPHON. Ktz. 



Filaments branched, distinctly vaginate, composed of gela- 

 tinous cellules, each enclosing a solid gonimic nucleus, arranged 

 in simple or 2-3-fold series within the vagina. 



1. S. compactus, Ktz. black, densely intricate, filaments 

 ascending, rigid, curved, coalescent below, vagina cartilagineo- 

 corneous, fuscous ; cellules in single series. 



On rocks, frequent. 1876. 



Syn :— Kutzing Sp. Algarum, 316. (1849). 



Fig :— Hassall Algaa, t. 68. f. 3. 



Geog. Disteib : — Europe. 

 ^Bot. Prov:— 26. 



* Ireland : — Rocks south side of Kylemore Lake, eo. Galwaj, Mr. Larbalestier. 

 (1876. ) 



II. GONIONEMA. Nyl. 



Thallus filiform, granula gonima concatenated into a single central 

 axis. Apothecia concolorous, biatorine. Spermatia minutely oblong, 

 simple. 



I. G. velutinum, Nyl. dark-brown, slender, entangled ; apothecia 

 dark-brown, terminal, centre depressed, margin swollen, pale within; 

 spores 8, cokmrless, ellipsoid, simple ; paraphyses slender. 



On sub-alpine rocks rare. 1864. 



Stn :-Nyl. Prodr. 16 (1857) ; Syn. 88 ; Scand. 23 ; Collema, Ach. Syn. 329. 



Pig :— Ann. and Mag. Nat. Hist. July 1865, t. 4, f, 1, 2, 3, 4, 5. 6 : Nyl. Syn. 

 t. 1, f. 11. 



Exs :— Arn. 571. Lojka. 1590. Sinrft. 71. Reich. & Schub. 69. 



Geog. Distrib : — Europe, Scandinavia, Prance. 



Bot. Prov:— 1.7. 



England : — St. Cleere near Liskeard, Messrs. Turner & Sowerby. 



Wales : — Barmouth ! Craig Breidden ! (northern precipices) Montgomery- 

 shire (1864) ; Snowdon ! Cwm Bochlwyd ! Cwm Idwal ! Cwm Cywion ! Aran 

 Mowddy ! 



" Gelatina hymenea I. blue, then vinous-red. Spores .009 — .010 mm, long, 

 •007 mm. hvoaA." (Nyl.) Spores .013— .014 mm. long, .007 mm. broad. 



Fam : II. COLLEMACEI. 



Thallus black, fuscous, dark olive, rarely cinerascent or glauces- 

 cent, variable in form ; granula gonima either moniliform or 

 variously dispersed in the gelatinous substance of the thallus. 

 Apothecia generally lecanorine, rarely biatorine, rarely endocarpoid, 

 generally rufescent, rarely black, internally whitish or pale, 



