Part 2, 1917] AMARANTHACEAE 123 
ovoid, 1-1.5 mm. long, thin, smooth, indehiscent, green or reddish; seed obovoid or rotund, 
0.8-1 mm. in diameter, smooth, black and shining. 
TyPe Locauity: Not definitely stated. 
Distrrpurion: Along streams, in mud or sand, South Dakota, Michigan, and Ontario to 
Tennessee, 
8. Acnida tamariscina (Nutt.) Wood, Bot. & Fl. 289. 1873. 
Amaranthus tamariscinus Nutt. Trans. Am. Phil. Soc. II. 5: 165. 1837. 
Montelia tamariscina A. Gray, Man. ed. 2.370. 1856. 
Plants glabrous throughout; stems stout, erect, 5-15 dm. high, green or glaucescent, 
striate-angulate or smooth, simple or much branched, the branches ascending; leaves few, the 
petioles slender, 0.6-5 cm. long, the blades usually oblong to lance-oblong, sometimes lanceolate 
or ovate, 1-10 cm. long, 0.4-3.5 cm. wide, rounded or obtuse at the apex, acute to attenuate 
at the base, pale yellowish-green above, paler beneath; staminate inflorescence of simple 
terminal or axillary spikes, or of narrow naked panicles composed of few slender, densely 
flowered, erect or drooping spikes 5-20 cm. long and 8-10 mm. thick, the spikes sometimes 
interrupted below; pistillate inflorescence of few terminal and axillary spikes, or a broad panicle 
composed of numerous slender, densely flowered, rigid or flexuous, erect or spreading spikes 
3-40 cm. long and 6-15 mm. thick; sepals 2.5-3 mm. long, oblong to ovate, acuminate to 
obtuse, mucronate, l-nerved, green along the nerve, equaling or longer than the bracts; bracts 
of the pistillate flowers linear to lanceolate, longer than the utricle, attenuate to rigid, pungent, 
spreading or recurved tips, green; stigmas 3; utricle 1.5 mm. long, globose-ovoid, thin-walled, 
smooth or somewhat tuberculate, circumscissile; seed 0.6—0.8 mm. in diameter, rotund, lenticu- 
lar, smooth, dark reddish-brown, shining. 
TYPE LOCALITY: On the sand beaches of the Arkansas and Grand rivers. 
DISTRIBUTION: Damp or dry fields, South Dakota to Missouri, Kentucky, Texas, New Mexico, 
and Colorado; adventive in Pennsylvania, New Jersey, and Delaware. 
ILLUSTRATIONS: Britt. & Brown, Ill. Fi. f. 1410; ed. 2. f. 1671. 
7. ACANTHOCHITON Torr. in Sitgr. Rep. Exp. 170. 1853. 
Glabrous erect branched annual herbs. Leaves alternate, petiolate, entire. Flowers 
dioecious, glomerate, the glomerules spicate. Staminate flowers ebracteate, the bractlets 
minute or wanting; sepals 5, subequal, lance-oblong, acuminate, l-nerved; stamens 5, the 
filaments filiform, distinct, the anthers oblong, 4-celled. Pistillate flowers concealed by 
large rigid cordate foliaceous bracts, these spinulose at the apex, recurved; bractlets minute 
or elongate, rigid, and setaceous, or lanceolate; perianth none; ovary ovoid, slightly compressed, 
the stigmas 2-4, capillary; ovule 1, erect, on a short funicle. Utricle oval, compressed, mem- 
branaceous, circumscissile. Seed erect, obovoid, compressed, smooth, shining; embryo 
annular, the endosperm farinaceous; cotyledons narrow; radicle inferior. 
Type species, Acanthochiton Wrightii Torr. 
1. Acanthochiton Wrightii Torr. in Sitgr. Rep. Exp. 170. 1853. 
Plants stout, 1.5-8 dm. high, much branched, the branches ascending, the lowest ones 
sometimes decumbent, striate; petioles 3-20 mm. long; leaf-blades linear to oblong or lance- 
oblong, 2-8 cm. long, 2-12 mm. wide, rounded at the apex, cuneate or attenuate at the base, 
the margins crispate, the veins prominent beneath, whitish; sepals 3 mm. long, the apex 
aristate; staminate flowers in elongate, nearly naked spikes, the pistillate fascicles axillary 
and in stout, nearly naked, terminal spikes; bracts of the pistillate flowers 5-15 mm. long, 
indurate in age, acuminate to a spinulose tip, reticulate-veined, the margins dentate or crenu- 
late; seed 1-1.3 mm. long, dark reddish-brown. 
Bil peo Oo in sandy soil, western Texas and northern Chihuahua to 
northeastern Arizona. 
ILLUSTRATIONS: Sitgr. Rep. Exp. ol. 13; E. & P. Nat. Pfl. 3!8: f. 57. 
