THE LICHEN FLORA OF THE SANTA CRUZ PENINSULA 253 



On charred stems of Manzanita in the mountains near Los Gatos, 

 at about 2000 feet altitude. 



9. RINODINA ROBORIS (Duf.) Th. Fr. 



Lecanora roboris Duf our, Pr. L. Gall. 93. 

 Rinodina roboris Jatta, Syll. Lich. Ital. 273. 1900. 



Thallus thin, determinate to sub-effuse, of rather uniform small 

 areoles; color whitish to gray; hypothallus broad, black, but often 

 obsolete; KOH faint yellow; CaCl 2 2 -. 



Apothecia medium to large, sessile, soon convex, the gray, entire 

 margin becoming crenulate, rarely entirely disappearing; the disk 

 blackish brown; paraphyses agglutinate, their tips enlarged and pale 

 yellow; epithecium brownish; hypothecium clear; thecium a beauti- 

 ful dark blue with I; spores long ellipsoid, thin- walled, -5 //. 



19-27 



On bark oiAcer macrophyllum and of oaks, along the summit of the 

 range. 



Found in western Europe and on the Pacific coast of the United 

 States. 



Differs from sophodes in the color of the thallus, the larger apothe- 

 cia with crenulate margin, and the larger spores, as well as the thai- 

 line reaction with KOH. 



\ 

 10. RINODINA EXIGUA (Ach.) Th. Fr. 



Lichen exigua Ach. Lich. Suec. Prodr., 69. 1798. 



Rinodina exigua Th. Fr. Lich. Scand. I: 201. 1871. 



Rinodina exigua Tuck. Syn. N. Am. Lich. I: 208. 1882, in part. 



Thallus effuse, thin, uneven, granulose, or merely scurfy, and often 

 scattered and very thin; varying in color from whitish and pale gray 

 to very dark grayish brown and blackish olive; KOH ; CaCl 2 O 2 . 



Apothecia small to minute, numerous, plane or finally convex, disk 

 brownish black to black; thalline margin pale or whitish, from entire 

 becoming crenulate, and finally excluded; epithecium blackish 

 brown, granulose; paraphyses thread-like, free, their tips enlarged, 

 yellowish brown; hypothecium clear; thecium blue with I; spores 



6 - ii 



- V. 

 ii. 5 - 20 



