122 PROCEEDINGS OF THE AMERICAN ACADEMY 



are thin in texture, and in both that species and C. scirpoidea the spike 

 is single. 



A. FiVi/o/iCE, Tuckerman, Enum. Meth. 8. (Scirpince, Txii-km. I.e.) Spike one, 

 androgynous or in C. scirpoidea commonly unisexual. 



184. Carex scirpoidka, Michx. Fl. Bor.-Am. ii. 171. 

 C. Michauxii, Schwein. An. Tab. 



C Wormskioldiana, Horuem. Fl. Dan. t. 1528. 



C. Wormskioldii, Drejer, Rev. Crit. Car. 18. 



C. scirpina, Tuckerman, Enum. Meth. 8. 

 High mountains of N. New England and northward to Greenland, 

 and N. Michigan and northwestward ; mountains of Colorado, Utah, 

 Nevada, Montana, etc. Adjacent Asia. Norway. 



185. Carex filifolia, Nuttall, Gen. N. Am. PI. ii. 204. 

 Uncinia hreviseta, Torr, Monogr. 428. 



Kohresia globularis^ Dewey, Sill. Journ. xxix. 253. 

 Dry plains, Colorado to California and northward into British 

 America. 



Var. VALID A, Olney, in herb. ; Bailey, Coulter's Man. 374. 



Colorado. G. filifolia, van, Boott, Proc. Acad. Philad. 1863, 77. 



Var. ? miser. 



C. Lyoni, Olney, Bot. King's Rep., et al., not Boott. 



Low, usually two to four inches high, the leaves very rigid : pistil- 

 late portion of the spike not conspicuous : pistillate scales much 

 narrower than in the species, the margins scarcely hyaline : perigy- 

 nium much smaller and flatter, entirely concealed under the scale, 

 oblong-obovate, smooth, — Alpine: Clover IMts., Nevada, alt. 10,000 

 ft., Watson 1220; Berthoud Pass, Col., Vasey 591, Twin Lakes, 

 Wolfe 1001, and Parry 442, coll. of 1862, lat. 39°- 41°. Fully 

 mature specimens are a desideratum. C rupestris is at once distin- 

 guished from this by its flat leaves. 



B. Montana, Fries, Corp. 188. Spikes two to several, the lowest occasionally 

 long-peduncled and radical ; perigynium rounded, contracted above and 

 below, mostly bearing two prominent ribs. — A puzzling group, best illus- 

 trated by C. Pennsylvanica, C. umhellata, and tbeir immediate allies. 



* Perigynium abruptly rounded above, bearing a more or less prominent rib on each side, 



186. Carex Pennsylvanica, Lamarck, Diet, de Bot. iii. 388. 

 a marginata, Muhl. ; Willd. Sp. PL iv. 261. 



C. lucornm, Willd. Hort. Berol. Suppl. 63. 

 Stoloniferous, forming large patches : leaves usually as long as the 

 slender culms (which are commonly less than ten inches high), narrow, 



