288 CLVi. CYPERACE^ (clarke). [KyUinga. 



Var. Kelleri, C. B. Clarke, Spike and spikelets rather smaller. Nut-bearing 

 glumes elliptic, subtriangular at the tip, not at all acuminate. 

 ITlle Xiand. Somaliland: Abdallah, JTeZZer, 80 ! 87! 



2. PYCREUS, Beauv. Fl. Owar. ii. 48, t. 86, fig. 2. 



Spikes umbellate or solitary, or of only 1 spikelet. Spikelets 5-40- 

 flowered ; glumes distichous, 2 lowest empty, several succeeding bi- 

 sexual and perfecting nuts, caducous in fruit from the lowest upwards ; 

 rhachilla persistent, not winged. Stamens 3-1, anterior ; anthers 

 narrow-oblong, not crested. Style passing continuously into the top 

 of the pistil, not bulbous at the base ; branches 2, linear in a plane 

 passing: through the rhachilla. Nut ellipsoid or obovoid, compressed 

 laterally. — Glabrous. Leaves all close to the base of the nodeless stem 

 (in species 9-11 the stem is more clothed by leaf-sheaths in its lower 

 ' half), green and long. Spikelets in ebracteolate (rarely bracteolate in 

 P. alhojnarginatus) clusters or spikes arranged in bracteate umbels ; 

 bracts similar to the leaves, only smaller. — Gyperus, Benth. et Hook. f. 

 Gen. PI. iii. 1043 partly. 



Species 63 ; in all tropical and warm-temperate regions, a few extending 

 to Canada and Amurland. 



^ZoNAT^. — Superficial cells of the nut longitudinally oblong or elliptic. Nut 

 often appearing zonate or muricate by reason that the thickened ends of the cells run 

 into an undulating or broken horizontal line. 

 Annuals. 



Spikelets yellow or reddish, hardly at all chest- 

 nut-coloured. 

 Spikelets yellowish, with parallel sides . . 1. P.flavescens. 



Spikelets reddish-brown, lanceolate . . 2. P. intermedins. 



Spikelets yellow, brown-spotted, elliptic 5. P. pauper. 



Spikelets chestnut -brown. 



Leaves and stems slender . . . . 3. P. rehmannianus. 



Leaves and stems capillary . . . . 4. P. dehilissimus. 

 Perennials. Rhizomes or stolons frequent. 



Spikelets \ in. wide . . . . ' . 7. P. suhtrigonus. 



Spikelets ^ in. wide at least. 



Stems and leaves slender . . . . 6. P. nigricans. 

 Stems stouter ; leaves thicker . . . 8. P. macranthus. 



**Ptjncticulat^. — Superficial cells of the nut nearly square. Nut often appear- 

 ing dotted very regularly, by reason of the light reflected from the convex surface of 

 each cell. 



Stems dlothed for \-^ their length by leaf-sheaths, 

 decumbent at the base. • 

 Spikelets turgid, greenish-brown, tinged dark- 

 red 9. P. sanguinolentus; 



Spikelets flattened, hardly turgid ; glumes not 

 inflated. 

 Glumes green with black nerves . . .10. P. afronervatus. 

 Glumes rich or pale brown .... 11. P. Mundtii. 

 Stems enveloped by the leaf-sheaths only a little 

 way above the base. 



