148 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Inflorescence usually much longer than the leaves, many-flowered; leaves never 

 shining, at least the youngest ones more or less white-mealy. 

 Leaves bright green, slightly mealy when young; seeds 1.5-2 mm. broad. 



4. C. paganum. 

 Leaves white-mealy; seeds 1.5 mm. broad or smaller 5. C. album. 



1. Chenopodium ambrosioides L. Wohmsbed. 



Waste ground, especially along streets and about barnyards; common. July-Oct. 

 Widely distributed in N. Amer. and in the tropics of the Old World. (C. antkelminti- 

 cumL.; C. ambrosiovles anthelminticum A. Gray.) 



The seeds, "American wormseed," are used medicinally. 



Chenopodium botrys L., Jerusalem oak, with sweet-scented leaves, was reported 

 from Washington by Ward, but has not been collected recently. 



2. Chenopodium boscianum Moq. 



Woods; infrequent. June-Oct. Eastern U. S. 

 3 Chenopodium murale L. . Nettle-leaf goosefoot. 



Common along streets. July-Oct. Native of Eur.; now widely dispersed in 

 most civilized regions. 



C. urbicum of Ward's Flora doubtless belongs here; the latter species is not known 

 from our region. 



4. Chenopodium paganum Tleichenb. 



Moist ground; common. June-Oct. Native of Eur.; now widely naturalized in 

 the U. S. (C. viride of most authors, not of Linnaeus.) 



Specimens of this were once reported from the District by Steele as C. rubrum 

 L., a quite different species that is not known to occur here. C. lanceolatum Muhl. 

 is a form, or perhaps a species, with narrow leaves. 



5. Chenopodium album L. Lamb's-quarters. Pigweed. 

 Waste and cultivated ground; an abundant weed. June-Oct. Native of Eur. 



but now widely naturalized in N. Amer., or it may be in part native. 

 The young plants are used as "greens." 



2. ATRIPLEX L. 



1. Atriplex hastata L. 



Common in the streets of Alexandria; rare in waste ground about Washington. 

 July-Oct. Widely dispersed in the U. S.; our plants probably adventive from Eur. 

 (A. patula hastata A. Gray.) 



3. SALSOLA L. 

 1. Salsola kali L. Saltwort. 



Reported from Alexandria by Ward. Frequent along the Atlantic coast of N. Amer. 

 and in Eur. 



47. AMAEANTHACEAE. Amaranth Family. 



Leaves opposite; flowers white; plants perennial 1. IRESINE. 



Leaves alternate; flowers green or reddish; plants annual. 

 Fruit fleshy, 3-5-angled, indehiscent; pistillate flowers without sepals; plants 



pistillate and staminate; leaves lanceolate 2. ACNIDA. 



Fruit thin and dry, not angled, dehiscent; pistillate flowers with sepals; pistillate 

 and staminate flowers on the same plant; leaves usually broader than lanceolate. 



3. AMARANTHTTS. 



