176 HERRE 



and excluding the thick entire or crenate margin; sometimes crowded 

 and then angular; disk flesh-colored and gray pruinose; spores 



7 ~~ 9 



broadly ellipsoid. - - /* ; thecium blue with I. 



12-15 



Common on bark of trees in the foothills and on fences in the salt 

 marshes about San Francisco Bay. Collected by Bolander at Ala- 

 meda, by Howe at Berkeley, and by Dr. Hasse in southern California; 

 Calif ornian specimens also in Tuck. Herb., collected by Charles 

 Wright. A North American lichen. 



7. LECANORA ATRA (Huds.) Ach. 



Lichen ater Hudson, Fl. Angl. 1 : 445. 1762. 



Lecanora atra Ach. Lich. Univ. 334. 1810 (excluding vars. /? and f)> 



Lecanora atra Tuck. Syn. N. Am. Lich. I: 189. 1882. 



Thallus from determinate becoming effuse and spreading exten- 

 sively, bounded by the black hypothallus; from rather thin soon 

 becoming thick, granulate, rough warty, or passing into smoothish 

 distinct areoles, separated by black fissures; color a clear bright gray- 

 ish white varying to cloudy ashy gray; KOH yellow; CaCLj0 2 . 



Apothecia from innate soon prominent, sessile, and finally quite 

 large; disk plane or slightly convex, dead black; margin persistent, 

 white, entire, rarely crenulate or flexuous ; black within to the naked 

 eye; paraphyses broad, coherent, dark violet, their tips much darker; 

 becoming reddish violet with KOH; blue or greenish blue with I; 



spores ellipsoid or ovate, /*. 



9-75 - i4 



The smooth, areolate, brightly colored form with large to very 

 large apothecia is abundant and conspicuous on shale along the sea 

 coast north of Santa Cruz for 30 miles or so. Found also on rocks in 

 the foothills and sometimes on old fences, the thallus strongly resem- 

 bling that of Lecanora coilocarpa. Collected on metamorphic sand- 

 stone at Mission Dolores by Bolander. In the Tuckerman Her- 

 barium is a Californian specimen collected by Charles Wright on 

 Quercus agrifolia, but I have been unable to find it on trees. 



Occurring all over the North Temperate Zone. 



