THE LICHEN FLORA OF THE SANTA CRUZ PENINSULA 207 



A lichen of the cool temperate and alpine regions of Europe and 

 North America. 



3. CETRARIA CHLOROPHYLLA (Humb.) Wainio. 



Lichen chlorophylliis Humboldt, Fl. Fr. Spicil. 20. 1793. 



Cetraria chlorophylla Wainio, Lich. Caucas. in Termesztr. fiizetek, 



22: 278. 1899. 

 Cetraria chlorophylla Herre, Proc. Wash. Acad. Sci. 7: 338. 1906. 

 Cetraria saepincola b. chlorophylla Tuck. Syn. N. Am. Lich. I: 35. 



1882. 



Thallus foUaceous, expanded; lobes numerous, short, irregularly 

 cut; terminally ascendant, sinuate, crenate, with white sorediate 

 edges; color varying from olivaceous or greenish dull brown to a 

 shining chestnut, and darker; beneath paler, wrinkled, and with 

 occasional scattered fibrils. 



Always sterile with us and rare in fruit anywhere. 



On Pseudotsuga taxifolia, Castle Rock Ridge, altitude 2500 feet. 

 Common on fences throughout the foothills and to the summit of 

 the range, but originally apparently confined to the larger coniferae 

 of the redwood formation. 



Recognized at once by the narrow but conspicuous white edge of 

 the thallus. 



A plant of northern and central Europe and western America. 



4. CETRARIA GLAUCA (L.) Ach. 



Z,fc/fe« g/awcw5 Linne, Sp. Plant. 2 : 1148. 1753. 

 Cetraria glauca Ach. Meth. Lich. 296. 1803. 

 Cetraria glauca Tuck. Syn. N. Am. Lich. I: 35. 1882. 

 Cetraria glauca Herre, Proc. Wash. Acad. Sci. 7: 339. 1906. 



Thallus membranaceous, foliaceous, sinuately or irregularly 

 broad-lobed; the crenate or dissected edges of the lobes frequently 

 sorediate, thickened, and prolonged into more or less conspicuous 

 coralloid branchlets; color of plants growing on earth: greenish 

 gray marginally, varying to olive- or brown-gray centrally, or some- 

 times the whole plant a glaucous gray-green; beneath wrinkled or 

 reticulate and black, with now and then a chestnut margin; fibrils 

 wanting, or occasionally scattered and very minute. Color of 



