460 PROCEEDINGS OF THE AMERICAN ACADEMY, 
brunnescens they are distinctly beaked, of more membranous texture, and 
usually with serrate margins. . 
The commonest form of Carex canescens in North America is the 
plant mentioned without name by Francis Boott and figured by him 
in his Illustrations, IV. table 496. This unique American form, which in 
essential characters is like true C. canescens, differs in its elongated in- 
florescence, 5 to 15 dm. long, at least the lower spikelets very remote. 
The plant seems to have been generally treated by American authors a8 
typical C. canescens, and no published name is available for it. 
The following synopsis. presents the characters and ranges of the 
northeastern Hyparrhenae as now understood by the writer. In 1s 
preparation he has studied the material in the Gray Herbarium and the 
herbarium of the New England Botanical Club ; as well as the hundreds 
of sheets in the herbarium of the Geological Survey Department of 
Canada, kindly placed at his disposal by Mr. James M. Macoun ; those of 
the Olney Herbarium of Brown University, made accessible to him by Mr. 
J. Franklin Collins; and a series from the Fairbanks Museum at St. Johns- 
bury, Vermont, rich in forms of the scoparia group, specially accumulated 
by the director, Dr. T. E. Hazen, for detailed study, and then generously 
forwarded to the writer. He has also been greatly assisted by the - 
of material from the private herbaria of the Honorable J. R. Churebill 5 
President Ezra Brainerd; Doctors C. B. Graves, J. V. Haberer, G. G. 
Kennedy, and C. W. Swan; and Messrs. Luman Andrews, C. H. Bissell, 
Walter Deane, E. L. Rand, W. P. Rich, and E. F. Williams. The 
identification of dubious species of Willdenow and of Schkuhr has been 
facilitated by the codperation of Dr. J. M. Greenman while at the Roy al 
Botanical Museum in Berlin, and by Prof. Carl Mez of the University 
of Halle; and authentic material of the late Dr. E. C. Howe's Carex 
seorsa has been generously furnished by Prof. C. H. Peck. 
HYPARRHENAB, Fries. Staminate flowers scattered or at ye 
base of the uniform spikelets (only in exceptional individuals and in the 
often dioecious C. gynocrates and C. exilis the entire spikelet staminate)- 
Key to Species.’ 
* Perigynia with thin or winged margins. a 
+ Perigynia ascending, the tips only sometimes wide-spreading or recutve® 
not spongy at base, the margins winged at least toward the beak. 
1 The perigynial characters are here based on study of mature plants. ie 
r 
eral the perigynia at the tip of the spikelet are less characteristic than those ett 
the middle ; and, if possible, the latter alone should be used in critical comparis© 
