294 GENUS ATRIPLEX. 



25. ATRIPLEX PENTANDRA (Jacquin) Standley, N. Am. Fl. 21:54. 1916. Plate 46. 



Decumbent or sometimes erect annual or perennial herb or the base suffrutescent, 1 

 to 8 dm. high, branched throughout to form a spreading bushy plant often of irregular 

 outline; branches obtusely angled or nearly terete, not striate, sparsely scurfy but early 

 glabrate and then stramineous, the pale bark persistent but breaking longitudinally on 

 old stems; leaves all alternate, except probably the lower, with very short petioles or the 

 upper ones sessile, elliptic to spatulate or obovate, rarely lanceolate, tapering or rounded 

 at the base, obtuse or acute at apex, commonly mucronate, 0.5 to 4 cm. long, 0.2 to 15. 

 cm. wide, entire or sinuate or acutely dentate, thin, sparsely scurfy and greenish on the 

 upper surface, densely white-scurfy beneath, or white on both surfaces in some island 

 forms (subspecies confinis), 1-nerved; flowers monoecious, the staminate glomerules 

 either solitary or in terminal spikes up to 3 cm. (or more?) long, the pistillate flowers in 

 small axillary glomerules and sometimes mixing with the lower staminate; perianth 

 5-clef t in the staminate flowers, wanting in the pistillate ; fruiting bracts sessile or short- 

 stalked, compressed, united to about the middle, obovate or orbicular-obovate, com- 

 monly with broad thin margins, 2.5 to 6 mm. long, 3 to 6 mm. broad, sharply and saliently 

 dentate above the middle, the faces variously crested or tubercled or smooth, often reticu- 

 late-veined ; seed 0.8 to 1 .5 mm. long, brown ; radicle superior. {Axyris pentandra Jacquin, 

 Sel. Stirp. Am. 244, 1763.) 



Mexico and States bordering the Gulf of Mexico to the West Indies and along the 

 Atlantic Coast to New Hampshire, also in South America. 



SUBSPECIES. 



Artificial Key to the Subspecies of Atriplex pentandra. 

 Leaves sparsely scurfy and greenish on the upper surface; fruiting bracts mostly crested or 

 tubercled. 

 Bracts 3 to 6 mm. long. Eastern. 



Leaves broadly elliptic to obovate; bracts 4 to 6 mm. long. Virginia to New England, (a) arenaria (p. 294). 

 Leaves elliptic to lanceolate or linear; bracts 3 to 4 mm. long (rarely 4.5 mm.). 



Eastern Mexico to West Indies and the South Atlantic States (6) lypica (p. 294). 



Bracts 2.5 to 3 mm. long (rarely 3.5 mm.). Western (d) muricata (p. 296). 



Leaves densely and permanently white-scurfy on both sides; fruiting bracts (about 3 mm. 



long) not crested or tubercled. West Indies (c) confinis (p. 295). 



25a. Atriplex pentandra arenaria (Nuttall). — Stem erect from an annual taproot, 

 or the lateral branches procumbent; leaves elliptic to broadly oblong or obovate, tapering 

 to the base, obtuse or the upper acute at summit, 1.5 to 4 cm. long, 0.5 to 1.5 cm. wide, 

 typically entire or undulate, but often saliently dentate, at first gray or whitish-scurfy 

 on both sides, but soon greenish above; staminate spikes 3 cm. or less long; fruiting bracts 

 4 to 6 mm. long, 4 to 7 mm. broad, the sides with 2 dentate crests or tuberculate or rarely 

 smooth, reticulate-veiny or the veins covered by the tubercles; seed about 1.5 mm. long. 

 {A. arenaria Nuttall, Genera 1 : 198, 1818.) Sandy shores along the Atlantic Coast from 

 New Hampshire to Virginia and perhaps farther southward. Type locality, sandy sea- 

 coast of New Jersey. Collections: Hampton, New Hampshire, Robinson 73S (Gr); 

 Katama Bay, Marthas Vineyard, Massachusetts, Fernald 75 (Gr, NY, UC, US) ; Groton, 

 Connecticut, September 9, 1903, Bissell (Gr) ; Atlantic City, New Jersey, Martindale 53 

 (US); tjrpe, Nuttall (Phila); Gardiners Island, Long Island, August 15, 1878, Miller 

 (US); Piney Point, Maryland, 1874, Vasey (US); Franklin County, Virginia, Brown 

 (Phila). 



256. Atriplex pentandra typica. — Stems spreading or reclining, but usually with 

 ascending or erect ends, from an annual or perennial root, often suffrutescent at base; 

 leaves elliptic to narrowly oblong or lanceolate, acute at each end or obtuse and mucro- 

 nate at summit, 1 to 3 cm. long, 0.3 to 1 cm. wide (short and broad in minor variation 



