..X 



GNETACEAE 65 



Pitt River; American River to Merced River (near Yosemite Valley) and south 

 to South Fork Kaweah. 



Refs. TORRKYA CALIFORNICA Torr. N. Y. Jour. Pharm. 3: 49 (1854), type loc. headwaters 

 Feather and Yuba rivers; Jepson, Silva Cal. 167, pi. 53 (1910). Tumion calif ornicum Greene, 

 Pitt. 2: 195 (1891) ; Sargent, Silva N. Am. 10: 59, t. 513 (1896) ; Sudworth, Trees Pac. Coast, 

 191 (1908). 



GNETACEAE. GNETUM FAMILY. 



Woody plants without resin, of very diverse habit. Leaves opposite or 

 ternate. Catkins unisexual, with imbricated bracts. Stamens 1, or several and 

 monadelphous, set within a membranous calyx-like perianth, the perianths ses- 

 sile in the axils of the bracts. Ovule solitary, surrounded by a very small urn- 

 shaped perianth and produced at apex into an exserted style-like process 

 (micropyle), the whole sessile at the summit of the catkin and subtended by 

 its bracts. Embryo axile in endosperm ; cotyledons always 2. Genera 3, the 

 remarkable Welwitschia of South Africa, Gnetum of the tropics, and Ephedra. 



1. EPHEDRA L. 



Equisetum-like shrubs with slender long- jointed stems, opposite or fascicled 

 branches and scale-like leaves. Leaves more or less connate, sheathing the 

 stem, at length splitting to the base. Staminate and ovulate catkins on differ- 

 ent shrubs. Stamens 2 to 8, united into a column. Ovulate perianth indurated 

 in fruit, perforated only for the passage of the micropyle. Species 30, desert 

 regions of both eastern and western hemispheres. (Greek ephedra, the name 

 used by Pliny for the horse-tails.) 



Scales and bracts in 2's; bracts connate at base; ovulate catkins (and sometimes the stami- 

 nate) on peduncles % to 4 lines long. 



Branches bright or yellowish green, erect and broom-like 1. E. viridis. 



Branches pale or glaucous, divergent 2. E. nevadensis. 



Scales and bracts in 3's; bracts distinct; ovulate catkins sessile or nearly so; branches clus- 

 tered, erect. 



Fruiting catkin subglobose, 3 to 4 lines long 3. E. californica. 



Fruiting catkin slender-ovate, 5 to 6 lines long 4. E. trifurca. 



1. E. viridis Cov. Erect green shrub iy 2 to 3 feet high, with numerous 

 broom-like muriculate branches; fruiting bracts green, firm, with narrow scari- 

 ous edge ; fruits 1 or usually 2 in ,a place, with flat faces and strongly convex 

 or carinate backs, 3y 2 to 4 lines long. 



Mountain slopes (5000 to 7000 feet alt.) of the desert ranges about the 

 Mohave Desert, Owens Valley and Death Valley, north to the White Mountains 

 and east through Nevada and Arizona to southwestern Utah. Also Ft. Tejon. 



Refs. EPHEDRA VIRIDIS Cov. Contrib. U. S. Nat. Herb. 4: 220 (1S93), type from Coso Mts., 

 Inyo Co., Coville 923. 



2. E. nevadensis Wats. Erect olive-colored shrub y> to 2 feet high; 

 branches somewhat scabrous, divergent; scales sheathing, at length mostly 

 deciduous; fruiting bracts ovate or round ovate, firm, scarious on edges, 4 to 

 6 pairs ; fruit exserted, 3 or 4 lines long, 3-ridged or trigonous, or, when 2 in a 

 place, with more or less flat faces and strongly convex or carinate backs. 



Desert valleys of the Mohave and Colorado deserts (2500 to 4500 feet alt.), 

 north to Honey Lake Valley and northern Nevada (Pyramid Lake, Lemmon), 

 south into Mexico and Lower California, and east through southern Nevada to 

 Utah. Also Kern Valley and upper San Joaquin Valley. 



Refs. EPHEDRA NEVADENSIS Wats. Proc. Am. Acacl. 14: 298 (1879), Bot. Cal. 2: 108 (1880). 

 E. antisyphilitica Wats. IT. S. Expl. 40th Par. 5: 328, pi. 39 (1871), not C. A. Mey. 



3. E. californica Wats. Stems decumbent or spreading, with numerous 



