OP ARTS AND SCIENCES. 299 



aments sessile or nearly so, of 4 to 6 pairs of connate bracts : fila- 

 ments long-exserted, united throughout or the anthers (4 to 8) shortly 

 stipitate : fertile flowers upon a scaly-bracted (rarely naked) peduncle 

 1 to G lines long ; bracts 4 or 5 pairs, round-ovate, connate : fruit 

 solitary or in pairs, 3 or rarely 4 lines long, exserted, acutish, smooth ; 

 micropyle a line long. — E. antisyphilitica, Watson, Bot. King. Exp. 

 328, t. 39. Throughout the interior from N. Nevada to the Colorado 

 Desert (Fort Mohave, Cooper), Northern Mexico (Gregg), and the 

 Rio Grande. The New Mexican form has more usually very short 

 peduncles and solitary fruit. Californian specimens collected at Fort 

 Tejon (n. 112, Xantus) and in the Santa Inez Mountains (n. 347, 

 Brewer), without flowers or fruit, are peculiar in having persistent 

 scales and may possibly prove distinct. 



Ephedra 1 Torreyana. Erect, 1 to 3 feet high or more, the 

 branches often somewhat flexuous, not spinose, usually ternate : scales 

 short (a line or two long), sheathing, ternate, with broad and acutish 

 or rarely narrow lobes, subpersistent, not becoming shreddy : staminate 



1 The North American species of this genus may be defined as follows : — 



* Scales 2-lobed and the branches (not spinose) opposite : bracts in pairs and evidently connate, 



scarcely at all scarious : fruit solitary or in pairs, smooth. 



1. E. antisyphilitica, C. A. Meyer. Stems mostly lax and slender, dedi- 

 cate and nearly prostrate or supported on shrubs or trees to a height of 8 or 10 

 feet ; bark not shreddy nor fibrous : scales distinct, subpersistent, very short and 

 triangular-ovate, or when young setaceously tipped and slightly sheathing (some- 

 times 2 lines long) : aments on short bracteate peduncles : filaments distinct 

 above the perianth : fertile flowers with 3 or 4 pairs of bracts : fruit 2i or 3 

 lines long: otherwise as the next, but micropyle slightly shorter. — W. Texas 

 and New Mexico (n. 320, 1590, Berlandier ; n. 673, 1881, Wright ; n. 225, 273, 

 428, Lindheimer), to Northern Mexico (n. 855, Parry & Palmer, 1878). 



2. E. Nevadensis, Watson. See above. 



* * Scales ternate and branches mostly in threes : bracts ternate, distinct or slightly connate, 



those of the fertile flowers more or less conspicuously scarious and unguiculate : fruit solitary 

 or in threes. 



3. E. trifurca, Torr. Erect, much branched, 2 to 6 feet high, the straight 

 rigid branches spinosely tipped : scales conspicuous, sheathing, 3 to 6 lines long, 

 sharply acuminate, persistent, becoming whitish and shreddy : staminate aments 

 on a very short peduncle, of 5 whorls of ovate bracts about equalling the 

 cuneate-oblong perianths : anthers (4 or 5) stipitate : fertile flowers nearly 

 sessile, 5 or 6 lines long, of numerous whorls (8 to 10) of very thin and scarious 

 entire round-cordate unguiculate bracts : fruit solitary, 6 lines long, 4-sided, 

 attenuate upward, smooth : micropyle 2£ lines long. — Arizona and New 

 Mexico ; Mohave Agency, Dr. E. Palmer (n. 523|, 1876) ; near El Paso, Dr. 

 Bigelow ; near Fronteras, Wright (n. 1884). 



4. E. Torreyana, Watson ; and 5. E. Californica, Watson. See above. 



