LICHENS OF SANTA CRUZ PENINSULA 373 



Occasionally abundantly fertile, especially on trees, but as a 

 rule apothecia are rare and scattered. 

 Lichen sciUalus Dickson, PI. Crypt. Brit. 3 : 18. 1793, excl. 



syn. 

 Peltigera scutata Leighton, Lich. Fl. Gt. Brit. ed. i. 210. 



1871. 



2. PELTIGERA RUFESCENS (Neck.) Iloffm. 



Thallus small or medium, ratber rigid and thick, smooth, 

 rounded, irregularly laciniate ; lobes more or less imbricate, 

 becoming narrowed, crowded, and somewhat crisped mar- 

 ginally ; color varying from pale greenish gray to reddish, 

 finally russet or dark brown ; pale brown beneath, reticulate 

 with thick brown veins ; these thinly sprinkled with coarse 

 brown fibrils. Apothecia often clustered ; comparatively large ; 

 terminal on long narrow lobes ; disk reddish brown and dark- 

 ening. 



On earth, moss, and rocks, in the foothills. 

 Lichen rufescens Necker, Meth. Muse. 79. 177 1. 

 Peltigera riifescens Hoffm. Deutsch. Fl. 2 : 107. 1795. 



3. PELTIGERA CANINA (L.) Hoffm. 



Thallus thin, orbicular, becoming expanded, irregular, and 

 very large ; lobes large, broad, imbricate, intricately cut ; tips 

 rounded or often more pointed, more or less deeply crenate. 

 Surface smooth, terminal margin sometimes with minute pubes- 

 cence, not visible except with a powerful magnifier. Apothecia 

 marginal, numerous ; circular, becoming elongate ; disk red- 

 brown ; color greenish gray or drab, varying to reddish or 

 brown. Beneath very pale, netted with pale, prominent veins 

 of the same color, these sometimes darkening centrally ; long 

 conspicuous concolorous or darkening fibrils present. 



Common on earth and moss throughout. 

 Lichen ca7nmcs 1^. Sy St. Nat. ed. 10. 1342. 1759; Fl. Suec. 



1109. 1755. 

 Peltigera canina Hoffm. Deutsch. Fl. 2: 106. i795- 



