THE LICHEN FLORA OF THE SANTA CRUZ PENINSULA 1 59 



KEY TO GENERA. 



Apothecia on the under surface of the marginal lobes. XL. Nephroma 

 Apothecia on the upper surface of the marginal lobes. XLI. Peltigera 



XL. Nephroma Ach. 



Nephroma Ach. Lich. Univ. loi. 1810. 



Thallus leafy, horizontally expanded, naked beneath or with 

 well developed rhizoids, with both sides corticated; alga Nostoc or 

 Palmella; under-side not netted veined. 



Apothecia reddish brown, circular to kidney-shaped; adnata to 

 the under side of the more or less extended and narrowed lobes and 

 usually exposed by the curling of the tips of the lobes; margin ab- 

 sent; spores 8, colorless or brownish, spindle-shaped to nearly needle- 

 like, 2-4 locular, straight or slightly curved. 



Species few, dwelling on bark and among mosses on rocks and 

 earth, in the cool temperate zone. 



KEY TO SPECIES. 



A. Under side of thallus with white tubercles, i. resupinatum rameum 

 AA. Under side not white tuberculate. 



B. Under side tomentose: medulla white, unaffected by KOH. 



2. helveticum 



BB. Under side smooth; medulla yellow, turning purplish red with 



KOH 3. lusilanicum 



I. NEPHROMA RESUPINATUM RAMEUM Schaerer. 



Nephroma resupinatum rameum Sch.a.eTer,Ermm. Crit. Lich. Europ. 



iS.pl. 2, f. 3. 1850. 

 Nephromium tomentosum rameum Nyl. apud Norrl. in Med. Sallsk. 



Faun, et Flora Fenn. 1: 18. 1876. 

 Nephromium to^nentosum rameum Herre, Proc. Wash. Acad. Sci. 



7: 370. 1906. 



Thallus expanded, membranaceous, medium to large; lobes 

 rounded, crenate, tomentose at the margin; becoming elevated a«d 

 finally imbricate and complicate; beneath covered with a pale 

 fleecy nap in which are many small white or yellowish tubercles, 

 these larger and more numerous on basal portion of lobes; color a 



