222 LTCHENACET. [PLATTSMA. 



Hah. On old pales and firs, very rarely on boulders, in hilly and 

 mountainous districts. — Distr. General and not uncommon in S., W., 

 and X. En^rland and the Highlands of Scotland : not seen from Ireland. 

 — B. M : Between Yarmouth and Caistor, Suffolk ; near St. Leonards 

 and Ifield, Sussex : IJay Tor, Devon ; Bardon Hill and Gopsall, Leicester- 

 shire ; Otelev Park, EUesmere, Shropshire: Cwm Bychan, Merioneth- 

 shire; Island of Auglesea ; Ingleby Park, Cleveland, Yorkshire ; Teesdale, 

 Durham ; Asho-ill, Cumberland. New Galloway, Kirkcudbrightshire ; 

 Glen Falloch, Killin. Ben Lawers, Glen Lyon, and Falls of Bruar, Perth- 

 shire ; Deerhill Wood and Kinnoul Wood, Forfarshire ; Morrone and Linn 

 of Quoich ( frt.), Braemar, Aberdeenshire ; Glen Xevis, Loch Ennich, and 

 Rothiemurchus Woods, Inverness-shire ; Lairg, Sutherlandshire. 



5. P. diflFusum Xyl. Flora, 1872, p. 247. — Thallus orbicular, ap- 

 pressed, closely adherent, isidioso-rugose in the centre, naked and 

 sinuato-lobed at the circumference, greyish- or brownish-white, 

 beneath pale brown, with a few long rhizin® : laciniae narrow, ap- 

 planate, multifid, rounded and crenate at the apices (K-|-deep yellow, 



CaCl~)- Apothecia small, subopaque, reddish-brown, the margin 



crenulate and sorediate ; spores ellipsoid, 0,006-9 mm. long, 0,005 

 -6 mm, thick. — Cromb. Journ, Bot, 1872, p. 234 ; Leight. Lich. Fl. 

 ed. 3, p. 95. — Parmelia diffusa Gray, Xat. Arr. i. p. 442. Lichen 

 diff'asvs Web. Spic. Fl. Gott. (1778) p. 250; Dicks. Crypt, fasc. iii. 

 17, t. 9. f. 6 ; With. Arr. ed. 3, iv. p. 32. Parmeliopsis alnirites 

 (Ach.), Cromb. Lich. Erit. p. 37. Parmelia aleurites Hook. Fl. Scot, 

 ii. p. 54 ; Sm. Eng. Fl. v. p. 203 ; :Mndd, Man. p. 98 ; Leight, Lich. 

 Fl. p. 130. Lichen aleurites Eng. Bot, t. 858. — To this is referable 

 Parmelia horrescens Tayl. in Mack. Fl, Hib. ii. p. 144 pro parte {cfr. 

 Cromb. Grevillea, vii. p. 98). — Brit. Exs. : Leight. n. 47; Mudd, 

 n. 71 : Dicks. Hort. Sic. n. 23. 



Xot unlike Parmeliopsis aleurites Xyl., but the sperniogones place it in 

 this genus. The thallus is often densely isidiiferous almost throughout, 

 onlv the apices of the laciniae being naked. It usually occurs sterile ; 

 when present the apothecia are elevated and numerous. The sperniogones 

 are large, black, marginal and tubercular, with spermatia 0,004 mm. long, 

 about 0,001 mm. thick. 



Hah. On old pales, rarely on stumps of felled trees in wooded lowland 

 and upland districts. — Dist:: Somewhat local in PZngland, X. AVa'es, and 

 the riighlauds of Scotland ; rare in S. W. Ireland. — B. M. : Henham, 

 Suffolk ; Penshurst, Kent ; ^^'akehurst, Sussex ; Croft Ca-tle and near 

 Hereford, Herefordshire ; near Wind.sor, Berkshire ; Stoke Park and 

 Sotterlv Park, Buckinghamshire ; Gopsall, Leicestershire ; near Oswestry 

 and EUesmere, Shropshire ; Cwm Bychan, Merionethshire ; Baysdale, 

 Cleveland, Yorkshiie. Barcaldine, Lome, Argyleshire : Inverarnan and 

 Crianl-arich. Perthshire ; Glee Dee, Braemar, Abei-deenshire ; Ilothieumr- 

 chus, Inverness-shire. Askew Wood and Dunkerron, co. Kerry. 



6. P. FaWunense NyL Syn. i. (1860) p. 309.--ThalIus suborbi- 

 cular, appresso-imbricate, smooth, laciniate, spadiceo-browuish or 

 brownish-black, beneath blackish, with a few rhiziuie at the cir- 

 cumference ; laciniae narrow, multifid, sinuate, subcanaliculate 



