Hawaiian Species of Carex — -KrAUSS 
275 
A B 
o 'fa c m. 
Fig. 1 6. Perigynia of Carex pluvia R. Krauss 
var. koolauensis R. Krauss. a, Hosaka 594; b, St. 
John 17978. 
purple; fertile culm 2-4 mm. wide, 50-100 
cm. long, erect, striate, scabrous on the angles 
above, smooth below; leaves brilliant red to 
purple at the base, light green above; sheaths 
ligneous, brilliant red to purple; inflorescence 
8-15 cm. long, erect, branching, 1-3 spikes 
to a node, 7-11 nodes to an inflorescence, the 
lower 2-3 internodes 2-3 cm. long, the up- 
per much shorter forming a dense head, each 
node enclosed by a leafy bract, the lower 30- 
45 cm. long, the upper shorter; peduncles of 
spikes 3-7 mm. long, enclosed by a purple, 
lanceolate ochrea; pistillate bracts equalling 
the perigynia, 2-3 white nerves along the 
dorsal keel, margins membranous, purple; 
staminate bracts lanceolate, 2-3 white nerves 
along the keel, margins membranous, purple; 
perigynia 1-2 mm. wide, 3-4 mm long, 
ridged, ovoid or narrowly oblong-obovoid, 
1-3 ridged or veined, shiny, purple to black, 
rostrum 1 mm. long, bidentate, stipitate; 
achenes bi-convex, obovoid, filling only half 
of the perigynium, rugose to smooth, yellow. 
Distribution: Oahu in Zone Du of Rip- 
perton and Hosaka (1942), the middle for- 
est, in wet areas in turf; usually with grasses. 
Type: Hosaka 594, Kipapa Gulch, 2,500 
feet, July 4, 1932. 
Specimens examined 
oahu: Fosberg 9730, Kipapa Gulch, 850 
m., Aug. 6, 1933; Fosberg and Hosaka 
13946, head of Kawaiiki Gulch and Kalua- 
nui Gulch, 900 m,, May 30, 1937; Hosaka 
594 (see type); St. John 17978, Hauula, 
Castle Trail, 2500', Apr. 25, 1937; Takata, 
Castle Trail, Kaluanui, 1000', Apr. 25, 1937. 
The variety koolauensis was first found by 
Edward Hosaka in 1932. It has been col- 
lected since in two other stations on Oahu. 
The variety shows transition with the species 
in Fosberg and Hosaka 13946 in that the 
purple-black covering of the perigynia is 
fully formed in some and just beginning to 
form in others. The perigynia are character- 
istically more narrow and more strongly stip- 
itate than those of the species. The two teeth 
of the beak are longer and more conspic- 
uously divaricate. With the small number of 
collections it seems unwise to classify the 
population as a new species, though its ap- 
pearance is considerably different. Its rarity, 
in turf in regions well populated by the spe- 
cies, suggests the possibility that it is a varia- 
tion resulting from an unusual combination 
of minor genetic differences as well as of 
ecological extremes. 
Carex alligata F. Boott, Illust. Genus Carex 
IV, 129, 1867. 
Figs. 17 a-f, 18 
Carex sandwicensis Boeckler, Flora, 265, 
1875. 
Carex Crustacea Nelmes, Kew Bull. I, 11, 
1946. 
Rootstocks caespitose; basal scales 8-15 
mm. wide, 3-12 cm. long, 3-6 per culm, 
fibrillose, brown to purple; fertile culm tri- 
angular in cross section, 3-4 mm. wide, 60- 
150 cm. long, erect, striate, scabrous on the 
angles above, becoming smooth below; leaves 
8-15 mm. wide, 20-120 cm. long, 4—8 per 
fertile culm, erect below, pendent above, 
V-shaped to flat, shiny, scabrous on the main 
