Dr. E. Stizenberger on the Saaxicolar Species of Opegrapha. 441 
mik. longee, 4-7 mik. crassee). Hymenium tinctura iodii ceeru- 
lescens. Spermogonia nigra punctiformia. Spermatia cylindrica 
(6-7 mik. longa, | mik. crassa). 
In rupibus granitaceis, schisto-talcaceis, et arenaceis Italie, Galliz, 
Angliz, Scandinaviee. 
7. Opegrapha saxicola, Ach. Syn. p. 71; Mass. Mem. p. 102 
(excl. syn. et var.); Nyl. Scand. 
O. rupestris, Pers. et Aut. O. sazatilis, Schar. pp.; Kremph. p. p. 0. 
gyrocarpa, Korb. p.p. O.rupestris vy. dolomitica, Arn. Exs. Sehar. 94; 
Hepp, 346; Leight. 243; Zw. 145 a; Korb. 197; Arn.104; Rabh.334. 
Thallus crustaceus effusus, continuus, tenuis, leprosus, albus v. gri- 
seus vy. czesius v. flavescens (interdum algis varie coloratus). 
Apothecia sparsa, nonnihil innata, leevia, rotundata vel elliptica, 
alterutro apice plerumqué obtuso vel abbreviato-linearia (1 millim. 
longa, ad 0-5 millim. lata), recta vel curvula, simplicia, rarius 
triradiata, rarissime tuberculato-difformia vel glyphiformia, nigra, 
margine primum rotundato, mox attenuato, acutiusculo, epithecio 
primum angusto tandem dilatato. Hymenium in hypothecio nigro 
vel hyalinum vel flavescens vel fuscescens, superne infuscatum 
(80-120 mik. altum), e paraphysibus filiformibus plus minusve 
liberis et ascis crasse claviformibus (60-80 mik. longis, 12-20 mik. 
latis), pariete apicali vix incrassato. Spore 8, oblongo-ellipticee 
vel clavatze, altero vel utroque apice rotundato, 3-septatee (20-30 
mik. longee, 5-8 mik. crassze), hyaline, rarius fuscee. Hymenium 
tinctura iodii vinose rubens. Spermogonia punctiformia, nigra. 
Spermatia cylindrica, tenella (5-6 mik. longa, 0°5 mik. crassa), 
in spermatophoris filiformibus. 
In rupibus arenaceis, calcareis et dolomiticis Italie, Helvetiz, Gallize, 
Angliz, Germanie. 
Var. Decandollei, Stizb. 
O. saxatilis, DC. Fl. Frane. (teste J. Mill. Genev.); Schar. p.p.; Mass. 
Mem. 102. O. saxigena, Tayl. O. rupestris, B. saxigena, Hepp. 
Exs. Leight. 311; Hepp. 347; Anzi, Longob. 406, Id. Venet. 104, 
A typo differt, thallo crassiore, albido, apotheciis magis immersis, 
minoribus (0°5-0°6 millim. longis, 0°2-0°4 millim. latis), ro- 
tundatis, insulatim confertis, margine tumido, persistenter rotun- 
dato, epithecio nunquam dilatato, ascis sporisque nonnihil minori- 
bus. Spermogonia et spermatia sicut in typo. 
In rupibus calcareis Italize, Helvetizee, Germaniz, Anglize. 
Obs. Nomen novum propter homonymiam nominum saxatilis et 
saxigenze cum nomine specifico allatum benevole excusare velis. 
Var. centrifuga, Mass. 
O. centrifuga, Mass. Misc. et Aut. Exs. Anzi, Venet. 102. 
Thallus effusus, farinoso-leproso-tartareus, cinereo-albescens vel cz- 
sius. Apothecia in annulos circulares disposita, nigra, splendentia, 
rotundata vel elongato-elliptica (0-5 millim. longa, 0:2 millim. lata); 
margine rotundato epithecium rimiforme nonnihil dilatatum ob- 
