Vol. 37 No 1 
BULLETIN 
TORREY BOTANICAL CLUB 
JANUARY, 1910 
A manual of the genus Usnea, as represented in North and 
Middle America, north of the 15th parallel 
R. HeBer Howe, Jr. 
(WITH PLATES I-7) 
In my “ Preliminary review of the genus Usnea”’ (Bull. Torrey 
Club 36 : 309~327. pl. 27-23. 1909), based on a long field and labo- 
ratory study of the plants as represented particularly in New Eng- 
land, I made no attempt to cast aside the nomenclature adopted by 
Tuckerman, the recognized authority for American workers. I 
intimated then, however, that a broader study of the genus, with 
the application of the present rules of nomenclature, would lead 
no doubt to a better understanding and hence to a more lucid 
taxonomy. I have now reached a point where the continuous 
use of a carefully determined classification finds no inadequacies, 
and I therefore see no reason to withhold its publication for a 
longer period of time, as I believe it soundly based and likely 
therefore to meet with general adoption, at least by the broader 
and more conservative workers. It is in no way new, but rather 
very old. 
A revision of the genus becomes necessary for three reasons : 
first, the current use of a nomenclature that is illegitimate accord- 
ing to the accepted rules; secondly, the unwarranted use of the 
specific term daréaza, fulfilling at least a sectional, if not almost a 
generic conception ; and, lastly, the hopeless misunderstanding of 
species and subspecies, evidenced by the >xtensive synonymy. 
Linnaeus’ species Lichen plicatus, L. barbutus, L. hirtus, and L. 
[The cil for December, 1909 (36: 651-720) was issued 28 D 1909. } 
] 
