266 GENUS ATRIPLEX. 



the bracts; fruiting bracts and seeds probably as in ^. dioeca but not known in mature 

 condition. 



Known only from the original collection from the dried bed of a lake in Bolson de 

 Mapimi, Chihuahua, April 13, 1847, Gregg (Gr). 



SYNONYM. 



This species has been transferred to Endolepis, taking there the name E. monilifera Standley (N. Am. Fl. 

 21:73,1916). 



RELATIONSHIPS. 



This species is so close to A. dioeca that on the basis of known characters the two 

 might almost be united. It differs principally in the proportionately wider leaves, the 

 dense staminate spikes, the more open and spreading perianth of the staminate flowers, 

 and the densely mealy foliage. The wide geographic separation of the two suggests that 

 further differences may be found when more abundant and fully mature material is 

 available for study. The status of the genus Endolepis, to which this species has been 

 referred, has been mentioned under A. dioeca. 



ECOLOGY AND USES. 



Nothing is known of the ecology and uses of this species. 



11. ATRIPLEX PHYLLOSTEGIA (Torrey) Watson, Proc. Am. Acad. 9: 108, 1874. Plate 40. 



Arrowscale. 



Erect annual herb, 1 to 4 dm. high, branched throughout to form a rounded or pyram- 

 idal bushy plant, in some cases less widely branched and the plant then narrow and 

 nearly columnar; branches slender, nearly terete, faintly striate, sparsely furfuraceous or 

 glabrate, the pale bark persistent; leaves all alternate except one or two lower pairs, 

 petioled or sessile, rhombic-triangular or hastate to broadly ovate or lanceolate, the ter- 

 minal portion commonly elongate-lanceolate and acute or acuminate, obtuse or cuneate at 

 base, 1 to 4 cm. long, 1 to 3 cm. wide, entire, thick and succulent when fresh, green, 

 sparsely furfuraceous but glabrate, chartaceous when dry; flowers monoecious or the 

 plants wholly pistillate, the staminate in small axillary glomerules near the ends of the 

 branches, the pistillate clustered in all of the axils except the upper when these bear 

 staminate flowers; perianth 5-cleft in the staminate flowers, sometimes present in pis- 

 tillate flowers and then consisting of 1 to 4 scales as long as the seed or often much 

 shorter; fruiting bracts sessile or subsessile or sometimes on stalks up to 15 mm. long, 

 compressed, united only near the base, lanceolate or lance-oblong, often from a hastate 

 cordate or winged base, the free tips attenuate and widely separated, 5 to 20 mm. long, 

 3 to 5 mm. wide at base, entire or deeply laciniate, the sides smooth, except for the 3 

 prominent ribs and cross-veinlets, or variously appendaged, the appendages sometimes 

 linear and up to 4 mm. long; seed 1.2 mm. long, brown; radicle superior. {Obione 

 phyllostegia Torrey in Watson, Botany King's Expl. 291, 1874). 



Sandy soil, western Utah, Nevada, southeastern Oregon, and eastern California, 

 extending across Tehachapi Pass and northward in the San Joaquin Valley nearly to 

 Tracy. Type locality, between the Truckee and Humboldt Rivers, western Nevada. 

 Collections: Gate of Gibraltar, Utah, June 3, Engelmann (NY); Dairy, Klamath County, 

 Oregon, alkali basin, Applegate 452 (Gr); Margin of Silver Lake, Lake County, Oregon, 

 Cusick 2787 (Gr, UC); Steamboat Springs, Nevada, Lemmon 11^2 (Gr); Truckee Pass 

 and Hot Spring Mountains, Nevada, Watson 986 (Gr, types) ; Wadsworth, near Clarks, 

 Nevada, June 15, 1897, Jones (Herb. Jones, type of A. draconis Jones, minor variation 2); 

 CaUfornia: near Keeler, Inyo County, Coville and Funston 875 (US, type of Endolepis 

 covillei Standley, minor variation 3); Antelope Valley, Davy 2196 (UC); Kern Lake, 

 San Joaquin Valley, Davy 21S9 (UC); Chowchilla, Madera County, Hall 11788 (UC). 

 Additional localities are cited in table 25. 



