BIPORT OF THE STATE BOTANIST 135 



prolongation, or the lowest setaceous or leaf-like; perigynia 

 ovate, nerved at the base, minutely punctate, whitish, tapering 

 into a short bifid or entire beak, divergent at maturity, a little 

 longer than the ovate, acute or obtuse scale ; achenium elliptical. 



Swamps and low wet places. Very common. May, June. 



Readily determined by its silvery spikes and -glaucous-green foli- 

 age. Small, slender forms with fewer flowered spikelets, but 

 glaucous foliage approach the following variety. A form occurs 

 in Suffolk county in which the terminal spikelet is wholly stami- 

 nate or bears but few perigynia. 



Yar. vulgaris Bailey. Differs from the type in its more slender, 

 erect, or diffuse stems ; its narrower, green, not glaucous, leaves ; 

 its fewer and smaller spikelets, with fewer flowers, and in its 

 green, horizontally-spreading perigynia with more pronounced 

 beaks and shorter scales. 



Tar. alpicola Wahl. Stems 6-15' high, firm, erect or spreading; 

 leaves green, 1" wide; spikelets 3-5, globular, 6-15 flowered, the 

 lowest sometimes with a filiform bract 2-24^' long, sometimes the 

 next above with a bristle-shaped bract ^' or more in length ; 

 perigynia green with brown spots or tawny ; otherwise as in the 

 preceding. A lowland form has capillary stems 15-20' high, 

 leaves V wide or less ; perigynia green slightly dashed with 

 brown. 



Spikelets 3-8 (single in Is) ovoid or oblong, approximate above, 

 interrupted below, or all scattered ; perigynia slightly concave, 

 rough or smooth-rairgined, nerved or nerveless, usually strongly 

 reflexed at maturity ; bracts bristle form or rarely the lowest 

 leaf-like. 'Plants rather rigid, green, often becoming yellowish 

 with age. In all the species of this group the terminal epikelet 

 appears to be stalked, the lower part being much contracted and 

 clothed with the scales of the staminate flowers. 



Perigynia ovate, small 1 



Perigvnia ovate or ovate lanceolate, large 2 



1 Spikelets scattered; perigynia with a sliort smooth beak. . . seorsa. 

 1 Spikelets contiguous or approximate, perigynia rough- 

 beaked interior. 



2 Si)ike]et single, sometimes wholly fertile or wholly sterih*. exilis. 



2 Spikelets approxini ite or scattered sterilis. 



