I 68 HERRE 



6. PERTUSARIA LECANINA Tuck. 



Pertusaria lecanina Tuck. Genera Lichenum, 126, footnote. 1872. 

 Pertusaria lecanina Tuck. Syn. N. Am. Lich. I: 213. 1882. 



Thallus sub-orbiculate, small, thin, smooth, becoming fissured 

 and more or less thickened or roughened centrally; gray to pale yel- 

 lowish; KOH pale yellow; KOH plus CaCl 2 O 2 deeper or orange- 

 yellow. 



Apothecial warts numerous, small, lecanorine, sessile, pruinose, 

 nearly concolorous to pure white; when moistened and rubbed the 

 pale and flesh-colored disk becomes visible; margin entire; spores in 



37. ; - 60 

 twos, - /*. 



74 - 1 60 



Abundant on the bark of Msculus californicus and Populus sp., 

 in the foothills; occasional on oaks. 



An inconspicuous species usually occurring in small to very small 

 patches among other crustaceous lichens on bark and obscured by 

 them. Apparently confined to California. 



7. PERTUSARIA PUSTULATA (Ach.) Nyl. 



Porina pustulata Ach. Lich. Univ. 309. 1810. 



Pertusaria pustulata Nyl. Act. Soc. Linn. Bord. Ser. III. 441, pi. 



I. 1856. 

 Pertusaria pustulata Tuck. Syn. N. Am. Lich. I: 215. 1882. 



Thallus small, smooth at first, soon chinky and more or less 

 roughened or warty, thin, and from determinate becoming effuse; 

 cream-colored, gray, or white; KOH ; CaC^C^ . 



Apothecial warts small to minute, convex, flattened, hemispheri- 

 cal or irregular; ostioles dusky or black, dot-like, often confluent and 

 becoming disk-like, or stellate; spores one or two in the asci, 





73-98 



Common on trunks and limbs of Quercus agrifolia about Santa 

 Cruz. Occasional on other trees in the foothills. A cosmopolitan 

 lichen. 



8. PERTUSARIA LEIOPLACA (Ach.) Schaer. 



Porina leioplaca Ach. Vet. Ak. Handl. 59. 1809. 



