Howe: American Species of Alectoria 107 



1831; Cetraria Fr. 1831 ; Bryopogon Link 1833; Atestia Trevis. 

 1861 ; Oropogon Th. Fr. 1861 ; Eualectoria Th. Fr. 1871 ; and 

 Hyalospora, Hyalodidyma, Phaeospora Sacc. 1882. 



The genus is represented in our area throughout the Trans- 

 itional and Boreal zones by at least ten distinct species. 



Following each species I have appended a list of North Ameri- 

 can material examined. A large number of European specimens 

 examined I have not thought necessary to list. To the curators 

 of these herbaria I wish here to express my sincere thanks for the 

 privilege of examination. The abbreviations within parentheses 

 are used in the citation of specimens. In this practice I am fol- 

 lowing the excellent precedent set by Dr. L. W. Riddle in his 

 recent work on the genus Stereocaulon. 



1. Herbarium of the U. S. National Museum (NH). 



2. Herbarium of Dr. J. W. Eckfeldt in the Academy of Natural Sciences, 

 Philadelphia (ANS). 



3. Herbarium of the New York Botanical Garden (NY). 



4. Herbarium of Wellesley College, Massachusetts (W). 



5. Herbarium of Prof. Bruce Fink, Miami University, Oxford, Ohio (F). 



6. Herbarium of the Portland Society of Natural History, Maine (P). 



7. The C. J. Sprague Herbarium in the Boston Society of Natural History (S). 



8. The Clara E. Cummings Herbarium, Wellesley College (CEC). 



9. Herbarium of the Boston Society Natural History (BSNH). 



10. Herbarium of Dr. L. W. Riddle, Wellesley, Mass. (R). 



11. Herbarium of the Sullivant Moss Chapter (SM). 



12. Herbarium of the University of Maine, Orono, Maine (UM). 



13. Taylor Herbarium, Boston Society of Natural History (T). 



14. Herbarium of Dr. H. E. Hasse, Sawtelle, California (HEH). 



15. Herbarium of Mr. C. C. Plitt, Baltimore, Md. (CCP). 



16. Herbarium of the Carnegie Museum, Pittsburg, Pa. (CM). 



17. Herbarium of Brown University, Providence, R. I. (B). 



18. Herbarium of the Canadian Geological Survey, Ottawa (CGS). 



19. Herbarium of Dr. A. C. Herre, Oakland, Cal. (ACH). 



The author's herbarium in tjie Thoreau Museum of Natural 

 History, Concord, Mass., is indicated by (H). 



Alectoria:* Ach. pro. parte, Lich. Univ. 120. pi. 13. f. 1-4. 



1810 



" Tree-hair," "Rock-hair," " Horse-tail Lichen" 



Description: Apothecia lateral, sessile, or on geniculations of 

 the branches, appendiculate (oregana) , scutelliform, convex, car- 



* From the Greek, meaning unmarried. 



