PR LAUDER LINDSAY ON NEW LICHENICOLOUS MICRO-FUNGI. 535 



Herbarium, they are flesh-coloured ; more generally they are grey. The 

 colour is always deepest at the apex, gradually disappearing below, where 

 the bodies of the columns coalesce into a chalky mass. The tips of the 

 papillae, which form the upper or free extremities of the columns, are generally 

 brown ; but this tint varies in depth or distinctness, being frequently very 

 obscure. 



D. Parasitic on thallus of Lecanora atra, Ach. 



Saxicolous : Pentland Hills, Edinburgh, Aug. 1855, W. L L. — No part of this parasite 

 gives a blue reaction with iodine. 



E. Parasitic on thallus of Diplotomma calcareum, Weis. 



Clapham, Yorkshire, Dr Carrington, Oct. 1857. — What appears to be the Coniotliecium is 

 seated on the thalline areolae, where they are at all distinct. It is black, generally 

 round, sometimes irregular in form, e.g., becoming sub-arthonioid ; generally flat ; 

 seldom, and only in young state, verrucarioid or papiltaform ; sometimes confluent; 

 superficial, the base only immersed. The parasite is sometimes indistinguishable from 

 the apothecia of its host, save as to the inferior size of the Coniotliecium; its size, how- 

 ever, is variable ; it generally wants the thalline margin — which is, however, sometimes 

 comparatively distinct, girding the apothecia. Here the Coniotliecium exhibits no 

 reproductive structure. 



The same Diplotomma is in England the seat of the parasitic Microtlielia rimosicola, 

 Leight. (Mudd, " Brit. Lich.," p. 308, plate v. fig. 129), which has 8-spored asci, and 

 oblong, 3-septate, brown sporidia. My note-book records, on the Yorkshire plant, the 

 presence of Pycnidia, containing stylospores. 



F. Parasitic on thallus of Lecanora cinerea, L. 



Kerry, Taylor (in Fl. Hibern., sub-nom. Spiloma splimrale). — Thallus of Lecanora sterile. 

 The parasite is scattered about the periphery of the alien thallus, much more abundantly 

 than the spermogonia of the Lecanora usually are. In the young state the Coniothedum 

 is immersed, and then frequently resembles closely some forms of the spermogonia of 

 L. cinerea; but gradually it becomes emergent and epithalline, resembling, according 

 to its size and form — whether flattish or sub-globose — the black apothecial disks of a 

 sessile Calicium or a Lecidea. It contains no reproductive structure, exhibiting under 

 the microscope only its deep-brown, basal, cellular tissue. 



G. Parasitic on sterile conditions (which are variously isidioid or variolarioid) of the thallus of 



several Lecanora. 

 It is in general impossible to determine in these cases what is the species of Lecanora. 



Sometimes only it appears to be L. glaucoma, L. paretta, or L. tartarea. In no case is 



the isidioid condition so marked as to bring the thallus under the category (C) of Isidium 



corallinum.* 



(a) Scuir-na-gillean, Skye, Aug. 1856, W. L. L. — Black papillae of parasite 

 very variable in size ; generally very distinct. Spores of a sooty-brown 

 colour. 

 (7/) Saxicolous : Moors east of Reykjavik, Iceland, June 1860, W. L. L. — Here, 

 again, no distinct reproductive structure is visible. The parasite is large, black, 

 and conspicuous by contrast of colour on the whitish or grey thallus, having 

 somewhat the characters of the apothecia of a Lecidea of the parasema or contigua 

 group ; much more irregular in form, however, and variable in size ; consist- 

 ing, moreover, apparently of aggregations, or glomeruli, of irregular papilla? ; 

 semi-immersed in the thalline areohe, but projecting by an irregular, rough, 

 granular surface above their level. 



(c) Morchone, Braemar, Aug. 1856, W. L. L. — Abundant and in fine condition. 



(d) North Wales, Rev. H. Davies (sub-nom. Isidium microsticticum, E. B. and 



Lich. Brit.) in Herb. Kew. — Parasite seated on, and partly in, small thalline 

 papillae ; in which latter case it possesses a pale thalline border ; small, black, 



* I have recently (August 1869) found Coniotliecium frequent on the sterile saxicolous thalli 

 of Lecanone, both in the northern and southern Highlands, e.g., Helmsdale, Sutherlandshire, and 

 St Mary's Loch district, Selkirkshire. In these districts the thalli in question are most probably 

 referable to Lecanora parella or glaucoma, or both. On similar sterile thalli the parasite is common 

 throughout Scotland, and probably throughout Britain. 



