208 THE JOURNAL OF BOTATfY 



A. Frevostii (Fr.) Th. Fr. On dolomitic conglomerate, Shipham, 

 and on limestone, Mentlip (6). 



A. prvinosa form nuda (Nyl.) is not an uncommon form and 

 often occurs with the tvpe. Taunton and Chard districts (5), 

 Keighlev (63). 



P. lepfospora Nitsch. is often placed under P. miiUijnincta, but 

 is distinguished from it bv the reddish supplementary reaction of the 

 thallus to potash, the fewer apothecia in the verrucse and the smaller 

 spores. On mountain ash, Crovdon hill (5). On birch, Horner wood 

 (5). This sjjecies has not been previousl}^ recorded from the British 

 Isles. 



P. relcda (Turn.) Nyl. Exton (5), Artro valley (48).— Form 

 aBpergUla (Ach.) Cromb. Hodder's Combe (5), Artro Avood (48). 

 P. lactea (L.) Nyl. On shingle of beach near Minehead (5). 

 P. conwuinis var. leiotera Nyl. The thallus is thinner and the 

 apothecia are more discrete and less difform than in the type. On 

 oak, Orchard Portman (5). — Var. rui^estris D. C. On rocks. Mer- 

 ridge near Bridgwater (5), Harlech (48), Llanberis (49),Killin (88). 

 P. ceutliocarpa (Sm.) T. & B. On rock, Achmore, Killin (88). 

 P. leiopJaca form octospora Nyl. Puckington (5). — Yoriw jug- 

 land is Hepp. On trunk of old beech, Broomfield (5). The thallus 

 is white and the apothecial verrucse are nearer together than in the 

 type. 



P. scut ell at a Hue is a somewdiat provisional name given to sterile 

 plants whose thalli and soredia do not give anv colourations with 

 potash, chloride of lime, iodine, or with potash followed by chloride of 

 lime. It is not uncommon in Somerset and has been found in many 

 other parts of the British Isles. 



Thelotrema lepadiniim var. scutelliforme Ach. On old holly and 

 oak trees, Quantock Combes (5), Fritham (11). 



Urceolaria scruposa var. hryopliila form parasitica (Smrf.) = 

 f. lichenicola (M. et Fr.). On Cladonia pyxidata var. pocillum^ 

 sand dunes, Braunton (4), Berrow (6). 



Lecidea decip>iens (Ehrh.) Ach. On soil-cap of old calcareous 

 wall, Bruton (6). 



L. prcEvimata Nyl. Treborough (o). 



X. granulosa form viridula Cromb. On peaty ground in orbicular 

 patches from a few inches to a foot in diameter, Skipwith Common 

 (61). Usually sterile. 



L.flexuosa (Fr.) Nyl. On pale, Loch Bi (98). 

 L. uliginosa (Schrad.) Ach. has for its algal symbiont Frotococcus 

 viridis, but occasionally Ghjeocapsai and other algie are present, and 

 may be actually included in th^ thallus. — Form humosa (Ehrli.) Ach. 

 Bare s»il of ])ank, Broomlield (JS). The spores in this specimen are 

 2o X 11-12/1 and lai-ger than those of the type from the same locality. 

 L. protrusa var. suhviridans (Nyl.) A. L. Sm. Merridge near 

 Bridgwater and Greenaloigh Point (5J. 



L. duhia (J3orr.) Hook. The differences between this species and 

 i. parasema \.Jlavcns are \qy\ slight. The more pulverulent thallus 

 has an orange colouration with chloride of lime, but this reaction also 

 occui-s in L. parasema, especially in the varieties elceocltroma and 



