226 PROCEEDINGS OF THE AMERICAN ACADEMY 



Nyl. 1. c. (Hillebrand). Common on trunks at low and medium 

 altitudes (Mann). 



Pannaria rubiginosa (Thunb.) Del. — Hawaii (Pickering), Tuck. 

 1. c. ; on the earth, summit of Hualalai, Hawaii, 8,000 feet alt., and on 

 trunks (Mann). 



Pannaria nigrocincta (Mont.) Nyl. — Oahu (Mann). 



Fam. 6. Lecanorei. 



Dirina repanda (Fr.) Nyl. — On lava, Oahu (Mann). 



Placodium cinnabarinum (Ach.) Anz. — On lava, Oahu (Mann). 



Placodium aurantiacum (Lightf.) Nseg. & Hepp. — Hawaiian 

 Islands (Remy), Nyl. 1. c. 



Placodium albidellum (sp. nov.) : thallo areolato-verruculoso 

 glaucescente ; apotheciis minutis sessilibus demum lutescentibus, disco 

 piano pulverulento, margine obtuso. Sporas octona? in thecis, medi- 

 ocres, polari-diblasta?, diam. 2-3 plo longiores, incolores. — On lava, 

 Oahu (Mann). — The rather obscure yellowish tinge at length observ- 

 able in the simple exciple is the only external feature associating this 

 Lichen with the group to which its spores refer it. 



Placodium Brebissonii (Fee, sub Lecidea). Lecanora^ Nyl. — 

 Hawaiian Islands (Remy), Nyl. 1. c. 



Placodium spadiceum (sp. nov.) : thalli granulis mox isidiomor- 

 pho-elongatis adscendentibus ramulosis dein stipatis cinereo-fuscescenti- 

 bus ; apotheciis mediocribus biatorinis sessilibus, disco piano castaneo 

 nudo, margine tenui elevato pallidiori subintegro, thallino obsolescente. 

 Sporae octonse in thecis, mediocres, ellipsoidere, polari-tetrablastas, diam. 

 2-3 plo longiores. — Trunks, Oahu (Mann). — Agrees with the last 

 species in exhibiting the highest known modification of its type of 

 spore, but differs remarkably in the isidioid evolution of its thallus, 

 and in the colors. The North American P. camptidium is perhaps 

 best comparable in the latter respect. 



Lecanora pallescens (L.) Schaer. — Trunks, Oahu (Mann). 



Lecanora glaucoma, Ach. — Volcanic rocks, Oahu (Mann). 



Lecanora subfusca (L.) Ach. — Oahu (Mann). 



Lecanora granifera, Ach. — Trunks, Oahu (Mann). 



Lecanora punicea, Ach. — Trunks, Oahu (Mann). 



Rinodina sophodes (Ach.) — Volcanic rocks, Oahu (Mann). 



Rinodina mamillana (sp. nov.) : thallo subtartareo rimoso-areo- 



