THE LICHEN FLORA OF THE SANTA CRUZ PENINSULA 67 



I. OPEGRAPHA SAXICOLA Ach. 



Opegrapha saxicola Ach. Syn. Meth. Lich. 71. 1814. 

 Opegrapha saxicola Stizenberger, Ueber die Stcinbew. Opegr.- 

 Arten, 23. 1865. 



Thallus effuse and very thin, or almost entirely disappearing, of 

 minute whitish, gray, or yellowish granules. 



Apothecia thickly or sparsely scattered, mostly bluntly ellipsoid, 

 or nearly circular, or compressed and sub-linear; straight or crooked; 

 dead black; margin at first thick and rounded, later thin, sharp- 

 edged, the disk then broadly visible; epithecium granulose, blackish 

 brown (reddish brown according to Stiz.); hypothecium broad, 

 dark brown; thecium colorless, slightly wine-red with I; paraphyses 

 threadlike, with tips not at all or very slightly thickened; asci 

 oblong or sub-clavate; spores 4-locular, ellipsoidal or ovoid, straight 



6 — 10 

 or rarely slightly curved, with a more or less evident halo, ,u; 



according to Stizenberger they are "wasserhell bis braun, 20 - 30 

 mik. lang und 5-8 mik. dick. " 



Spermogonia abundant, appearing as small or minute black dots; 

 spermatia small, short, 3.5 - 4 A< long. 



Abundant on sandstone near the old CUff House, San Francisco; 

 originally described from Europe, where it is widely distributed. 



Our plant is a variety, differing in several respects from typical 

 0. saxicola. 



2. OPEGRAPHA PROSILIENS Stirton. 



Opegrapha prosiliens Stirton, Grevillea, 3 : 36. 1874. 



Opegrapha prosiliens Leighton, Lich. Fl. Grt. Britain ed. 3, 403. 1879. 



Opegrapha prosiliens Hasse, Bull. So. Calif. Acad. Sci. 5:42. 1906. 



Thallus white, whitish, yellowish white, and yellowish-greenish, 

 thin to very thin, becoming almost or entirely obsolete, forming 

 small, variously shaped distinct patches, or effuse and spreading 

 indefinitely; KOH — ; CaCl202 — . 



Apothecia black, prominent, straight or curved, narrowly oblong 

 or ovoid, the margin broad, rounded, or rarely thin and erect, when 

 the disk is visible; disk ordinarily but a crevice; epithecium granu- 

 lose, dark brown; hypothecium from very dark brown merging into 

 black; paraphyses very slender, much branched and entwined, their 



