37 tf FLORA. 



Flowers all in small axilliary clusters, mostly shorter than the leaves. 



Plant prostrate ; sepals 4 or 5. 4. A. blitoides. 



Plant erect, bushy-branched ; sepals 3. 5. A. graecizans. 



Utricle indehisoent, membranous, coriaceous or fleshy. 



Upper flowers in terminal, more or less elongated spikes. 



Sepals 5, clawed ; flowers dicecious ; southwestern species. 



Bracts cuspidate-tipped, short. 6. A. Torreyi. 



Bracts subulate, long and sharp. 7. A. Palmeri. 



Sepals 2 or 3, oblong or spatulate ; flowers monoecious or polygamous ; in waste 

 places. 



Utricle smooth, dry, scarious. 8. A. lividus. 



Utricle fleshy, 3-5-nerved. 9. A. deflexus. 



Flowers all in small axillary clusters shorter than the leaves. 



Plant not fleshy ; stem prostrate ; leaves crisped. 10. A. crispus. 



Seacoast fleshy plant ; stem short, erect ; leaves not crisped. 



11. A. pumilus. 



1. Amaranthus retroflexus L. Rough Pigweed. (I. F. f. 1398.) Roughish- 

 puberulent, rather light green; stem stout, 0.3-3 m - ta 'l- Leaves ovate, rhombic- 

 ovate or the upper lanceolate, acute or acuminate at the apex, narrowed or cuneate 

 at the base, the larger 7-15 cm. long, their margins undulate or entire; flowers 

 green, densely aggregated in spikes, which are sessile, stout, ovoid -cylindric, 1-6 

 cm. long; bracts subulate, twice as long as the 5 scarious mucronate-tipped and 

 often emarginate sepals; stamens 5; utricle slightly wrinkled, rather shorter than 

 the sepals. A weed, throughout N. Am. except the extreme north. Also in Eu- 

 rope. Naturalized from tropical America. Aug. -Oct. 



2. Amaranthus h^bridus L. Slender Pigweed. (I. F. f. 1399.) Similar 

 to the preceding but darker green, or purple; stem usually slender, erect, 0.3-2.5 m. 

 tall. Leaves usually smaller; spikes linear-cylindric, axillary and forming dense 

 terminal panicles, ascending, somewhat spreading or drooping; bracts subulate, 

 twice as long as the 5 oblong acute or cuspidate sepals; stamens 5; utricle scarcely 

 wrinkled. A weed, in waste grounds, range of the preceding species, but locally 

 rare or absent. Naturalized from tropical America. Aug. -Oct. 



Amaranthus h^bridus paniculitus (L.) Uline & Bray. Flowers and foliage more or 

 less deeply tinged with red or purple; leaves sometimes lanceolate and bracts shorter. 

 Range of the type, but less abundant. 



3. Amaranthus spindsus L. Spiny Amaranth. (I. F. f. 1400.) Stem stout, 

 ridged, usually much branched, sometimes red, 3-12 dm. high. Leaves ovate, 

 rhombic-ovate or the upper lanceolate, acute at both ends, 2-8 cm. long, with a pair 

 of rigid stipular spines at each node, the midvein excurrent; flowers in numerous 

 capitate axillary clusters, and in dense terminal spreading or drooping spikes 2-15 

 cm. long; bracts lanceolate-subulate about as long as the 5 scarious oblong mucro- 

 nate-tipped 1 -nerved sepals, and the thin imperfectly circumscissile utricle; stamens 

 5. In waste and cultivated soil, Mass. to Penn., Ohio, Kans., Fla. and Mex. Nat- 

 uralized from tropical America. June-Sept. 



4. Amaranthus blitoides S. Wats. Prostrate Amaranth. (I. F. f. 1401.) 

 Stem diffusely branched, prostrate and spreading on the ground, 1. 5-6 dm. long, 

 often forming mats. Leaves obovate or spatulate. 6-25 mm. long, narrowed into 

 slender petioles; flowers in small axillary clusters; bracts lanceolate-subulate, little 

 longer than the 4 or 5 oblong-lanceolate acute or cuspidate sepals; stamens 3; utricle 

 nearly smooth, equalling or slightly longer than the sepals. In waste places, espe- 

 cially along the principal routes of travel, Me. to S. Out., Minn., N. J.. Mo. and 

 Kans. Naturalized from west of the Rocky Mts., where it appears to be indigenous 

 from Utah and Colo, to Mex. June-Oct. 



5. Amaranthus graecizans L. Tumble-weed. (I. F. f. 1402.) Glabrous, pale 

 green; stem erect, bushy. branched, whitish. 1.5-7 dm. tall, the branches slender, 

 ascending. Leaves oblong, spatulate or obovate, 1-4 cm. long, papillose, the mid- 

 vein excurrent; flowers polygamous, several together in small axillary clusters; 

 bracts subulate, pungent-pointed, spreading, much longer than the 3 membranous 

 sepals; stamens 3 ; utricle wrinkled, longer than the sepals. In waste and cultivated 

 soil throughout N. Am. Naturalized from tropical America. The leaves fall away 

 in autumn, and on the western plains the plant, thus denuded, is freely uprooted and 

 blown before the wind, whence the popular name. June-Sept. [A. albus L.j 



