LIST OF LICHENS. 537 



26. Lecanora polytropa (Ehrh,) var. illusoria 

 Ach., Tuck. Syn. i, 192 p. p. (Lecanora varia var. 

 folytrofa); on rocks. Yellowstone Park. 



27. Lecanora symmicta (Ach.) Nyl., Tuck. Syn. i, 

 192 p. p. Thallus red on application of hypochlorite 

 of lime; on dead wood. Sitka. 



28. Lecanora hypoptoides Nyl. in Flora 1867, 371; 

 on dead wood. Yellowstone Park. 



29. Lecanora pallescens (L.) Ach., Tuck. Syn. i, 

 196; on bark. Sitka. 



30. Lecanora coarctata (Sm.) Ach., Tuck. Syn. ii, 

 15: on rocks. Yellowstone Park. 



31. Ccenogonium interpositum Nyl. Coen. 91, Tuck. 

 Syn. i, 258; on thin twigs. Monterey. 



32. Lecidea meiocarpa Nyl. in. Flora 1876, 577; on 

 cones of cypress. Monterey. 



33. Lecidea sanguineo-atra (Ach.) Nyl., Tuck. Syn. 

 ii, 21, f. corticola; on thin twigs of coniferous trees. 

 Monterey. 



34. Lecidea MYRiocARPA (DC.) Nyl., Tuck. Syn. ii, 

 97; on cones of cypress. Monterey. 



35. Opegrapha atrorimalis Nyl. in Flora 1864, 488; 

 on cones of cypress and on thin twigs. Monterey. 



It still remains to add here the diagnosis of a new west- 

 ern lichen, kindly sent me by Mr. Henry Willey, New 

 Bedford, Mass. 



Alectoria pacifica Stzb. n. sp. 



Thallus fruticulous, prostrate, rigid, terete, smooth, 

 brown and shining, from i to 1.5 cm. in length, 1-1.5 

 mm. in width, very much divaricately branched, the 

 branches flexuous, densely intertangled, 0.25 mm. in di- 

 ameter, at the ends forked with very short branchlets, 

 scarcely 0.05 mm. in width, apothecia and spermogonia 

 unknown. 



2d Ser., Vol. V. (35) August 30, 1895. 



