Spikelets not all unisexual, some of the pistillate ones with 
stiur-im&te flowers. 
Spike lets in a simple spike, ........ 1* g. : irtella, 
Spikelets paniculate. 
Aohene very rugose. ...... 2. g* lieb;r,anpl . 
Aohen© smooth. 
Inflorescence long-exserted; achenee 1.5 Kin,, long and as 
broad, nearly truncate at apex. . 3* g. rnrdlei . 
Inflorescence little exserted; achenee 2*5 jam.* long, mxot 
longer than broad, rounded at apex, 
4. g. lithog-Dgrma . 
Spikelets all unisexual. 
Hargin of the disk (beneath the aohene) laoiniate or dilate< 
Kargin of disk laoiniate. 
Aohenes tuberoulate . ....... 5. g. sanloeidem . 
Aohenes smooth. 
Aohenes white. .......... 6, g. latifolia . 
Achenee purplish, ......... 7. g. jjqamdin—a . 
Margin of the disk ciliafe. 
Aohenee 5 to 6 iam* long; leaves 1.5 to 5 cm. wide, 
1 • S. sflTjj jto Bfc. 
Aohenes less than 3 a®, long; leaves 0*5 to 2 cm. wide. 
Disk long-cl lie. te with very numerous dark hairs; style 
base black or nearly so, , , 9* g* rA.tis . 
s 
Disk short-oiliate with few whitish hairs; style base 
light brown* ...... 10. g* microcarpa . 
Margin of disk neither laoiniate nor oiliate. 
Aohenes tuberoulate or reticulate. 
1 1 
