]96 LICHENES. [Squamaria. 



white smooth with large brownish central radiated fleshy warts, 

 apothecia concave rose-coloured with a thick elevated entire 



border Lecanora gelida, Ach. Syn. p. 186. — Lichen gelidus, 



Linn.— Dicks.— E. Bot. t. 699. 



On rocks in the north of England, particularly in Teesdale, and 

 Highlands of Scotland. 



14. S. lanuginosa, {powdery Squamaria); thallus orbicular 

 yellowish-white pulverulent greyish-black and downy beneath 

 lobes imbricated plane rounded slightly crenated, apothecia 

 reddish (of the same colour as the crust, Dicks.) their border 

 pulverulent. — Parmelia lanuginosa, Ach. Syn. p. 201. Hooh, 

 Fl. Scot. P. II. p. 53. — Lichen membranaceus, Dicks. Cr. Fasc. 

 2. p. 21. t.Q.f. 1. 



On rocks, in the Highlands of Scotland; not very uncommon. Appin, 

 Capt. Carmichael. 



15. S. dementi, (Clementine Squamaria); thallus adnate very 

 mealy with a membranous radiating lobed and finely cut margin 

 of a whitish unchangeable grey, apothecia bluish-black with an 

 inflexed crenate border. Sm — Parmelia dementi, Turn, in 

 Linn. Trans, v. 9. p. 146. t. 13./. 1. — P. Clementiana, Ach. Syn. 

 p. 201.— Lichen dementi, E. Bot. t. 1779. 



On trees and tiled roofs in Sussex, as well as about Tunbridge Wells 

 and Southampton, Mr. Borrer. 



16. S. ccesia, (grey-warted Squamaria); thallus orbicular con- 

 vex lobed and imbricated greyish- white its segments unequally 

 notched bearing powdery grey warts in the centre, apothecia 

 small glaucous-black concave with an elevated rather thick in- 

 flexed border. — Psora ccesia, Hoffm — Parmelia c&sia, Ach. 

 Syn. p. 216. — Lichen ca>sius, Ach. Prodr. — E. Bot. t. 1052. 



On walls, stones, and roofs of houses, in England. 



17. S. affinis, {spongy Squamaria); thallus orbicular livid 

 lead-colour with broad notched and cut lobes which are im- 

 bricated beneath somewhat spongy with bluish-black dense 

 fibres, apothecia rusty-coloured nearly flat with a thick elevated 



inflexed crenated border Lichen affinis, Dicks. Cr. Fasc. 4. 



p. 24. t. 12. f. 6. E. Bot. t. 983 Parmelia rubiginosa, Ach. 



Syn. p. 201. — Lichen rubiginosus, Thunb. Fl. Cap. p. 1^6? 



On trees, in subalpine countries, frequent.— I have retained Mr. Dick- 

 son's name, in preference to that of Thunberg, to which Acharius re- 

 fers it, under an idea that the African and Euuopean plant may prove 

 different. The species was called affinis, on account of its similarity 

 with Lichen (oiir Placodium) plumbeas: but however great the resem- 

 blance may be in the thallus, their apothecia are quite different. 



18. S. circindta, (circinate Squamaria); thallus adnate sub- 

 crustaceous in the centre orbicular greyish cracked marked 

 with radiant marginal lobe-like furrows, apothecia central 

 crowded depressed blackish-brown at length angular with a 

 smooth border. — Lecanora circinata, Ach. Syn. p. 184 — Lichen 

 circinatus, Ach. Prodr. — E. Bot. t. 1941. 



