(15 ) 
Lastarriza.—Perigonium tubular, coria- 
ceous, 6-dentate. Ovary 1. Fruit an 
akene. Involucre 0. 
Chorizanthe.—Involucre 1-3 flowered, 
coriaceous, 3-6 angular. Ovary 1. 
Fruit, an akene. 
Tricerastes (Datisca).—Calyx superior 
Petals 0. Anthers extrorse. Ovary 3- 
quetrous. Styles 3, each 2-cleft. Ovary 
1-celled. Placente parietal. 
Cyperus.—Glumaceous. Spiklets dis- 
tichous. 
Eleocharis.—Glumaceous. Spiklets im- 
bricate. Perigonial bristles not exserted. 
Caryopsis apiculate by the persistent 
articulate base of the style. 
Fimbristylis.—Glumaceous. Spikelets 
imbricate. Perigonial bristles-not ex- 
serted. Caryopsis apiculate. Style 
articulate above its base. Aquatic. 
Scirpus.—Glumaceous. Spiklets imbri- 
cate. Perigonial bristles not exserted. 
Caryopsis apiculate by the persistent 
continuous base of the style. Aquatic. 
Eriophorum.—Glumaceous. Spikelets 
imbricate. Perigonial bristles exserted, 
considerably longer than the glume. 
Aquatic. 
