Juncaceae 9] 
C.  Involucral leaf at least 1/3 shorter than the stem; stamens 3 or 6. 
D. Plants densely tufted from bunched rootstocks. 
FE. Stamens 3; perianth 2 mm. long; capsule clavate-obovate, retuse or 
obtuse, not apiculate. 
F. Perianth-segments green when young; inflorescence a loose panicle. W. 
° J. effusus L. (Hummock Rush) 
FF. Perianth-segments brown; inflorescence a dense paniclee W. E. 
(J. effusus bruneus.) 
J. effusus hesperius Pip. 
EE. Stamens 6; perianth 3 mm. long; capsule subglobose, obtuse, apiculate. 
Gers J. patens Mey. 
DD. Plants rather in lines along elongated rootstocks; stamens 6; ripe cap- 
sule acute ‘to obtuse, with sharp point. 
G. Mature capsule sharply triangular; sheaths at stem-base black. WG 
J. lescurii Bol. 
GG. Mature capsule bluntly triangular; sheaths at stem-base tinged with 
green or brown. W. C. E. 
J. balticug Willd. (Baltic Rush) 
CC. Involucral leaf about equaling the stem or longer; stamens 6. C. E. 
J. filiformis L. (Thread Rush) 
' BB. Plants 25 cm. or less high, alpine, caespitose; flowers 1—3; stamens 6. 
H. Inner leaf-sheaths at stem-base bristle-tipped; capsule acute. W.C.E. (J. 
drummondi. ) J. subtriflorus Cov. 
HH. Inner leaf-sheaths at stem-base leaf-bearing; capsule retuse. W. C. E. 
J. parryi Engelm. 
AA. Involucral leaf not appearing like a continuation of the stem, or if so conspic- 
uously channeled on the upper side, inflorescence usually appearing terminal. 
I. Leaves without cross partitions; either flat and with the flat side to the stem, 
or somewhat terete or hair-like and grooved. 
J. Stems either branched or less than 10 cm. long, leafy if long enough; annuals, 
bases soft, roots fibrous. 
K. Stamens 6; stems 2.5—30 cm. long, usually branched, leafy, with ped- 
uncles from the leaf axes. 
L. Capsule oblong. W. E. 
J. bufonius L. (Toad Rush) 
LL. Capsule globose.  E. 
J. sphaerocarpus Nees 
KK. Stamens 3; stems none or very short, with several scape-like peduncles 
2:5—/7.5, cm. long, 
M. Inflorescence 3—7-flowered; bracts several; style exserted. W. 
; J. triformis Engelm. 
MM. Inflorescence 1—3-flowered; bracts 2 or more; style and stigma 
included. E. (J. brachystylis.) 
J. triformis brachystylis Engelm. 
MMM. Inflorescence 1-flowered; bract 1; style exserted. E. (J. unci- 
alis.) J. triformis uniflorus Engelm. 
JJ. Stem mostly simple, naked or leafy; perennial, bases tougher, roots less fibrous. 
N. Flowers bracteolate, in a loose close panicle, but not in true heads. 
O. Capsule I-celled; perianth-segments acuminate; panicles various. 
