153 [ 7 ] 



desert west of the Colorado. A shrub 3-4 feet high, with numer- 

 ous slender branches; its appearance being that of Scotch broom, 

 (Spartium scoparium.) The sheaths are very long, 3-parted, with 

 subulate-acuminate segments. This can hardly be the E. America- 

 na of Quito, which is described as having 2-pa*ted sheaths. The 

 specimens are without either flowers or fruit. If the species should 

 prove to be new, it may be called E. trifurcus. There seems to be 

 still another species growing Qn the table lands of New Mexico, 

 differing from the preceding in its very short sheaths. 



Juniperus. Two undetermined species w T ere found in crossing 

 the country from the Del Norte to the Gila. Both of them have 

 the general character of J. Virginiana. One is a large tree, with 

 acerose leaves, and a bark like that of a Pinus; the other has short 

 closely appressed leaves, and berries larger than a buck shot. 



AMARYLLIDACE.E. 



Agave Americana, Linn. Found in descending the western slope 

 of the Cordilleras of California. This is the maguey of the Mexi- 

 cans. It shoots up a flowering stalk 10 or 15 feet high. The juice 

 of the plant affords an intoxicating drink called pulque. 



Another species of Agave, or.a very remarkable variety of the 

 preceding was found in New Mexico, west of the Del Norte. It 

 differs from A. Americana in its much shorter and broader leaves, 

 which are furnished wi^h smaller marginal spines. 



LILIACEiE. 



Yucca. The leaves only, of what appear to be four species of 

 this genus, occur in the collection, but we cannot identify them for 

 want of the inflorescence. 



ORCHIDACE,E. 



Spiranthes cernua, Rich. Low grounds in the valley of the Del 

 Norte. 



CYPERACEiE, 



Eleocharis quadrangulata, R. Brown. Valley of the Gila. 

 Cyperus Michauxianus, Schultes. Valley of the Gila. 



GRAMINEiE. 



Chloris alba, Presl. Spikes umbellate-fasciculate, numerous, 

 (8 — 12,) the peduncle enclosed in a broad compressed sheath; 

 spikelets 2-flowered; upper glume nearly as long as the flowers, 

 2-toothed, with a short awn between the teeth; lower palea of the 

 perfect flow r er obscurely 3-nerved, gibbous in the middle, the mar- 

 gin ciliate with long hairs towards the summit; awn three times as 

 long as the palea; neuter flower broad and truncate, inclosing a 

 short aristiform rudiment; the awn twice as long as the palea. Bed 

 of the Gila. Very near C. barbata, which differs in the entire 



