136 PYRENOPSIS. 



flat disk more or less reddish at least when wet ; the thin mar- 

 gin now granulate-coronate. Spores ellipsoid, simple, decelerate, 



^ mic. ; the paraphyses capillary, mostly conglutinate. Pan- 



naria, Mass. Eic. p. 14. Koerb. Parerg. p. 46. 



Calcareous . rocks. Illinois (Hall), Tuckerman Gen., 1874. 

 Trenton Falls, N. T., Willey. Alabama, Peters. 



Our plant agrees with an excellent Bavarian specimen ( Ar- 

 nold] from which I cannot, however, distinguish one of the two 

 (from the same substrate in Bavaria, Arnold] of Omphalaria 

 decipiens given in Anzi Venet. 2. The Italian specimens of the 

 present, so far as seen (Mass. Ital. n. 338 ; Anz. Langob. n. 430) 



are inferior. What I have seen of Psoroticliia murorum, 



Mass. (Mass. Lick. Ital. n. 300; Am. in herb. Koerb.), scarcely 

 makes clear the distinction between that lichen and Pyrenopsis 

 Schcereri. The latter is rather distinguished in the lowly group 

 before us by its well-characterized apothecia. 



2. P. melambola, Tuckerm.; thallus of exceedingly minute, 

 olivaceous granules compacted into finally thick and sub-stipi- 

 tate, scabrous, black areoles, and forming a close crust; apothe- 

 cia very minute, 1-6 in the areoles, innate, lecanorine, black ; 

 the thin margin persistent and of the same colour with the sub- 

 papillate disk. Spores ellipsoid, simple, decolorate, ^^ mic.; 



the paraphyses conglutinate. Synalissa, Obs. Lick. 4, I. c. 12, 



p. 170. 



Calcareous rocks, Alabama (Peters), Tuckerman I. c. 1877. 

 The regular, raised areoles now exceeding 1 millim. in width, 

 and almost reaching it in thickness ; the apothecia from O mm -, 1 

 to O mm -, 3 wide. 



3. P.polycocca (Nyl.) ; thallus of rounded blackish granules 

 soon passing into a broken, pitch-black crust which is hidden 

 mostly by the numerous apothecia ; these are very small, concol- 

 orous, globose, with a coarctate, punctiform, urceolate disk. 

 Spores ellipsoid, simple, decolorate, ^p mic., the capillary para- 

 physes conglutinate. Synalissa, Nyl. Syn. 1, p. 96. 



Granitic rocks, Vermont (Frost), Tuckerman in Nyl. I. c. 

 1858. Apothecia O mm -, 3 to O mm -, 4 wide. 



4. P. pliceococca, Tuckerm. ; thallus coralloid-granulose, com- 

 pacted into a thickish, broken crust like that of the last, but 

 reddish-brown ; apothecia scattered, very small, globose, concol- 



