532 DR LAUDER LINDSAY ON NEW LICHENICOLOUS MICRO-FUNGI. 



alike). Parasite very minute, punctiforni, black; basal cellular tissue deep 

 indigo-blue. Spore-filaments about -OOP' long, and -000111" broad. Spores 

 pale olive to bluish-black — about -00025" long, and -000111" broad. 



(c) Corticolous: Rathconnac, Co. Cork, Mar. 1858, Carroll. — On thalline areohc 

 and apothecia. Pai - asite resembles granules of a black powder dusted over 

 thallus, its blackness contrasting strongly with the brown disk of the apo- 

 thecium and white thallus of the Lccanora. Basal cellular tissue, like the 

 spores, bluish-black or indigo colour. Spore-filament, before separation of the 

 spores, 00066" long. It frequently throws off only two articulations from its 

 tip ; the lower or basal — that is, the longer — portion showing no division. 

 Sometimes there are three articulations or spores; rarely more. The mature 

 spores are -00025" long, and -00014" broad. 



(ct) Corticolous: Great Island, Cork, Mar. 1858, Carroll. — On periphery of 

 thallus. Spores pale olive or brown; oval, ellipsoid, or oblong; -00016" long, 

 and -000090" broad. 



(e) Corticolous: Carrigaloe, Cork Harbour, Mar. 1858, Carroll. Associated with 

 Physcia pulverulenta, Schreb. — Both on apothecia and thallus, on the latter 

 somewhat inconspicuous; apothecia degenerate; margin eroded; disk black- 

 punctate with the parasite, which is very numerous and crowded. The 

 Torula is here larger than is usual. Basal cellular tissue indigo-blue. Spores 

 brown ; -00025" to -00033" long, and 00016'' broad — usually simple. Asso- 

 ciated with the sporiferous filaments are numerous sterile or non-articulated — 

 probably abortive — colourless, very delicate and linear filaments, which re- 

 semble the paraphyses of many lichens. Sometimes they exhibit a faint appear- 

 ance of septa. A parallel to these sterile filaments is to be found in the sterile 

 hypertrophied sterigmata in the spermogonia of many lichens* 



(/) Corticolous: Upper Lakes, Killarney, Mar. 1858, Carroll. — Disk of apo- 

 thecia destroyed, and the apothecia converted into an uniform dark purple, 

 sterile, degenerate mass. 



(g) Corticolous : Ardrum, Carroll. — Basal cellular tissue deep indigo. Spore- 

 filaments -00133" long, -000111" broad; spores -00025" long, -000111"broad; 

 olive or bluish-brown ; oblong, with rounded ends ; simple, or frequently with 

 two polar spherical nuclei ; sometimes with double contour. 



(/<) Kerry : Taylor in Herb. Mackay. — On apothecia ; disks of which become sub- 

 convex and deformed, and frequently as black as those of L. atra, from growth 

 of the parasite. 



3. English or other forms. 



Betton, 1805, in Hei'b. Kew. All disks of the Lecanora entirely blackened by growth 

 of the parasite, so that the lichen is apt to be mistaken for L. atra. 



K'o'rber (" Parerga," p. 470) describes his Pharcidia congesta as very frequently para- 

 sitic on the apothecia of L. suhfusca and L. intumescens, Rebent., in Germany. It 

 possesses 8-spored asci ; the sporidia clavate-oblong, sub-baccillar, 1-3-septate, 

 hyaline. Lecidea parasitica, Flk., and Artlwnia varians, Dav., are also occasionally 

 parasitic either on the thallus or apothecia (or both) of L. suhfusca.^ 



B. Parasitic on thallus of Lecidea canescens, Ach. 



Corticolous : Aghada, Cork Harbour, Carroll. — On portions of thallus free of apothecia. 

 Basal cellular tissue bluish-black. Spores pale indigo-blue or olive ; terminal or larger 

 ones -00041" long,- -00016" broad ; others -00025" long, and -00011" to 00016" broad. 



C. Parasitic on thallus of Lecidea parasema, Ach. 



On a specimen in Herb. Kew, from Ireland (sub nom. Opegrapha gemmata, Ach.) Apothecia 

 of the Lecidea confluent and somewhat irregular in form and surface ; colour bluish or 

 greenish ; sporidia normal. The parasite presents very numerous individuals, closely 

 aggregated, occupying the site of, and otherwise externally resembling, spermogonia ; 

 very minute (microscopic), black, punctiform, superficial on, or more or less immersed 

 in, thallus of the Lecidea. Spore-filaments about - 0025" long, and -00016" broad, 



* Vide " Mem. Spermog." Plates IV. V. VI. VIII. XL XII. 

 t Vide Paper on " Parasitic Micro-Lichens." 



