Cypeni*. CYPERACE^E. 215 



spikes densely crowded : spikelets ovate-oblong, acute, 2 to 4 lines long : scales 

 acutish, obscurely 3-nerved, a line long or less : nutlet oblong, triangular, acute at 

 each end, brown, half a line long. C. sordidus, Presl, 1. c. 1 7 11 



In the valley of the Sacramento (Picker inrj); perhaps also collected by Haenke. Otherwise 

 known only in the Atlantic States from Delaware to Texas. 



4. Style 3-cleft and nutlet triangular : spikelets many-flowered, flattened with 

 carinate scales which are decurrent upon the rhachis as narrow wings: 

 spikes in compound umbels. PAPYRUS, Kunth. 



* Wings of the rhachis soon separating to the base, scarious and scale-like. 



Annuals. 



5. C. erythrorrhizos, Muhl. Sterns usually 1 to 3 feet high, stout, triangu- 

 lar, sometimes much reduced : leaves flat, 2 or 3 lines broad, those of the involucre 

 (4 to 8) greatly elongated : rays 4 inches long or less, bearing a cluster of sessile 

 simple or compound oblong spikes \ to 1 inch long : spikelets 2 to 6 (usually 3) 

 lines long, narrowly linear, numerous, spreading horizontally, nearly flat, bright 

 chestnut : scales oblong, obtuse, mucronulate, acutely carinate, i line long, exceed- 

 ing the light-colored round-ovate acutish compressed-triangular nutlet. C. cupreus, 

 Presl, Eel. Hrenk. i. 172. C. occidentals, Torr. Gyp. 259. 



Colorado Valley (Ncwberry); near Monterey (Haenke) ; Clear Lake (Bolander} ; near Sacramento 

 (Pickering, Greene); Oregon (Douglas, Hall, Howoll), and common in the Atlantic States. 

 Presl's species, as well as that of Torrey, was founded upon a very depauperate form. 



* * Wings of the rhachis persistently attached. 



6. C. phymatodes, Muhl. Perennial and fibrous-rooted, with slender root- 

 stocks bearing small globose tubers : stems rather stout, J to 3 feet high, triangular : 

 leaves nearly as long and involucral leaves elongated: umbel often compound, 

 4 _ j-rayed, the light chestnut-colored spikelets scattered and spreading in somewhat 

 distichous spikes (often an inch long or more), linear, acute, 3 to 12 lines long: 

 scales oblong, acutish, conspicuously several-nerved, thin and scariously margined, 

 rather acutely carinate, a line long or slightly more : nutlet oblong, obtuse and ob- 

 tusely triangular, f of a line long. C. repens, Ell. C. HcenJcei, Presl, 1. c. 1 



Var. Hermann!. Spikes contracted and more or less clustered at the summit 

 of the rays and iuvolucellate : spikelets sometimes bracteate. C. Hermanni, Buck- 

 ley, Proc. Philad. Acad. 1862, 10. 



Yosemite Valley (Bolander, a low form); San Luis Rey(Pa?ry); Fort Yuma (Thomas] ; Truckee 

 Valley, Nevada ( Watson), and frequent in the Atlantic States from Canada to Texas. The variety 

 has been found on Kern River (Hermann) and on the San Joaquiu, Lemirwn. The species resem- 

 bles 0. esculentus of the Old World (from the Mediterranean region to India), and has been re- 

 ferred to it by Boeckeler, Linn, xxxvi. 287. 



7. C. stenolepis, Torr. Resembling C. phymatodes in habit ; the straw-colored 

 spikelets more slender and with fewer (4 to 8) flowers, 3 or 4 lines long, somewhat 

 flattened or nearly terete at least when young, attenuate above ; rhachis with slender 

 joints : scales oblong, acutish, nearly 2 lines long, several-nerved, the lower usually 

 persistent after the falling of the spikelet : spikes usually rather dense, \ to 1 inch 

 long, in a more or less compound umbel : nutlet linear, nearly cylindrical, obtuse, a 

 line long, dark brown. Gyp. 263. 



In the valley of the Sacramento (Pickering); near Placerville (Rattan); in the southern Atlan- 

 tic States from North Carolina and Florida to Texas and New Mexico. 



5. Spikelets narrow, terete or nearly so, few to several-flowered, the scales closely 

 appressed and the broad wings of the rhachis embracing the triangular 

 nutlet : style 3-cleft. DICLIDIUM, Griseb. 



8. C. Michauxianus, Schult. Annual : stem usually | to 2 feet high but 

 often low : leaves 1 to 3 lines broad : involucres large : spikelets dull brown, some- 



