LICHENS OF SANTA CRUZ PENINSULA 377 



blackish green ; beneath concolorous or paler, lacunose, pitted 

 or fenestrate. Apothecia usually infrequent and scattered, 

 rarely numerous, small to medium ; the disk dark red-brown ; 

 the entire margin rather thick, finally excluded; often isidiose, 

 when it is tuberculate-radiate or toothed. 



On trees in the foothills. Fairly common. 

 Lichen uigrcscens Hudson, Flora Anglica 450. 1762. 

 Collema nigrcscens Wainio, Act. Soc. Faun. Fl. Fenn. 7 : 235 



1890. 



4. COLLEMA PULPOSUM (Bernh.) Ach. 



Thallus thin, small to medium size, orbicular or irregular, 

 closely appressed, usually depressed or concave centrally ; very 

 soft and gelatinous when moist ; lobes rounded, sometimes 

 imbricate, margin varying from entire and sinuous to crenate 

 and slightly laciniate or even denticulate ; surface smooth, more 

 or less pustulate and wrinkled ; sometimes beset with tiny erect 

 lobules ; color dark green or black ; sometimes brownish ; 

 beneath paler, smooth, wrinkled. Apothecia small, numerous ; 

 disk flat or concave, reddish, with paler entire margin ; spores 

 ovoid, from 4-locular becoming sub-muriform. 



On earth on damp hillsides, forming rather extensive patches 

 among mosses. Not rare in the foothills at an elevation of 

 about 1000 feet. 

 Lichen fiilfostis Bernhardi in Schrader's Journ. Bot. i : 7. 



p. I, /. I. 1799. 

 Collema fidposuni Ach. Lich. Univ. 632. 1810. 



5. COLLEMA LIMOSUM Ach. 



Thallus thin, small to medium, irregular or scattered, very 

 closely appressed ; margin irregularly crenate or dentate-lobu- 

 late ; surface smooth, or here and there beset with small ascend- 

 ant lobules ; color black or dark green. Thallus mostly dis- 

 appearing and becoming merely a net-work or margin about the 

 numerous large, imbedded apothecia ; disk mostly flat, reddish 

 or blackening; spores usually in fours in the thekes, ellipsoid, 

 muriform-plurilocular. 



On a wet clay bank beside a spring a mile above Wright's 



