1G7 



B. i)apillnta v. nlbo-ciiicta, Th. Fr Northwest. 



Opegiapha subvulgata, Nyl., Flora, 1869 Mexico. 



Grapliia pruinosa (Escliw.), Nyl., N. Gr. p. 5G4 Mexico. 



Segestria nucula v. granulata, Nyl., Antill., p. 22 Mexico. 



Verrucaria Campsteriana, Lindg. 1. c, p, 343 Greenland. 



[T/iis and V. tartaricola Linds. are prohnhly parasitic fungi.'] 



§ Pyrenula subelliptica, Tuck., Lea Cinciun. p. 47 Ohio. 



Phacopsis viilpina, Tul California. 



Opegrapha antiqua, Lesq., in Hayden's Report, 1873, pp. 370, 418, is the only 

 fossil Lichen as yet recorded on this Continent. 



CORRECTIONS. 



Umbilicaria mammulata, Ach.= U. spodochroa. 



U. polypliylla v. deusta = U. flocculosa Hoifm. 



Sticta creniilata, Del.= S. Ravenelii T. = S. erosa (Eschw.). 



Paunaria Michneri, T. = P. molybdaea Pers. f. 



Synalissa lignyota should be S. fuliginea (Wahl.). 



Lecanora coniza, T. = L. subf usca. 



XJrceolaria hybocarpa, T. = L. subfusca, f. 



Stereocaulon chlorellum, T. is not a species, the specimens belonging to Ram- 



alina. 

 Biatora leucoblephara, Nyl., perhaps does not differ from B. tricholoma, Mont. 

 Lecidea grossa, Pers. should be transferred to Heterothecium. 

 Arthonia pruinosa, Ach. = A. impolita (Elirh.). 

 Page 10, after No. 202, insert : 6. Spores muriform, plurilocular. 



Postscript. — Since these pages were sent to the printer, I have 

 had the opportunity of examining the Lichens collected by Dr. 

 Coulter, Botanist to the United States Exploring Expedition to 

 Colorado, during the summer of 1873. Among them are three 

 which are new to the United States, but occur in Europe, as follows : 



1 Solorina bispora, Nyl. 



2. Lecanora calcarea (L.), Smf., with an elegantly effigurate thallus. 



3. Endococcus erraticus (Mass.), Nyl. Parasitic on Placodium elegans. 



