Notes on Carex — III 
KENNETH KENT MACKENZIE 
” Carex latebrosa sp. nov. 
Carex Gayana hyalina Bailey, Proc. Am. Acad. 22: 135. 
1886. Not Carex hyalina Boott. 
Growing in dense clumps, somewhat stoloniferous, the culms 
3-9 dm. high, roughened on the angles, especially above, much 
exceeding the leaves. Leaves with well-developed blades usually 
three to six to a culm, all on the lower third, the blades 
8-35 cm. long, 1.5-4 mm. wide, flat or somewhat involute, 
roughened on the margins and towards the apex ; spikes linear- 
elliptic, 1 cm. long or less, from about seven to thirty, aggregated 
into a linear or linear-oblong head, 2-4 cm. long, 4-8 mm. wide, 
simple or slightly compound, the lower spikes more or less 
separate ; spikes largely and often entirely staminate, or usually 
bearing one to several perigynia at or near the base ; bracts absent, 
or the lower occasionally present, shorter than the head, some- 
what enlarged at base, acuminate or short-cuspidate ; scales ovate- 
lanceolate, from short-cuspidate to obtusish, usually acutish, straw- 
colored (without a trace of green at maturity), hyaline, wider and 
longer than the perigynia which are completely concealed (except 
where the scales get broken), the whole head appearing as a mass 
of straw-colored scales, with occasional dark spots, showing the 
concealed perigynia ; perigynia ascending, brownish at maturity, 
plano-convex, ovate (rather narrowly), 3.5 mm. long, 1.5 mm. 
wide, broadly rounded at base, tapering into the beak which is 
about one-half the length of the body, the body slightly spongy 
at base, nerved on the outer, nerveless but narrowly margined 
above on the inner surface, the beak serrulate, its apex in age 
somewhat bidentate; perigynia thin, readily separating from 
achenes at maturity; achenes lenticular, with suborbicular face, 
about 1.5 mm. long; stigmas two. 
Although referred by Professor Bailey as a variety to the North 
American plant which has been passing as Carex Gayana E. Desv. 
(Carex simulata sp. nov. infra), it seems to me that this plant is 
more closely related to some, of the forms of Carex marcida 
Boott. It does not possess the characteristic short-beaked perigy- 
nium of the former plant, and this has caused mos. specimens 
collected to be referred to the latter plant. However, it 1s readily 
