EUPHORBIACEAE QSPURGE FAMILY) 543 



4. ARGYTHAmNIA p. Br. 



Flowers monoecious. Calyx 5-parted, valvate in the staminate flowers, im- 

 bricate in the pistillate. Petals alternate with the calyx-lobes and with the 

 prominent lobes of the glandular disk. Stamens 5-15, united into a central 

 column in 1-3 whorls. Styles 1-3-cleft. Capsule depressed, S-lobed. Seeds 

 subglobose, roughened or reticulated, not caruiiculate. — Erect herbs or under- 

 shrubs, with purplish juice, and alternate usually stipulate leaves. (Name from 

 dp-yvpos, silver, and ddfxvos, bush, from the hoariness of the original species.) 



1. A. mercurialina Muell. Arg. Stem erect, nearly simple, 3-0 din." high, 

 sericeous ; leaves sessile, oblong-ovate to lanceolate, entire, pubescent with 

 appressed hairs or glabrate, somewhat rigid ; raceme many-flowered, exceeding 

 the leaves ; spatulate petals of the sterile flowers as long as the calyx-lobes • 

 ovary sericeous ; capsule appressed-pubescent, 8-10 mm. in diameter. (Ditaxis 

 Coult.) — Kan. to Ark. and Tex, 



5. MERCURIAlIS [Tourn.] L. Mercury 



Dioecious or monoecious. Flowers apetalous, in interrupted axillary spikes. 

 Stamens 8-20, distinct. Calyx small, green, globose in bud, 3-parted. Carpels 

 2(-3). — Herbs, with opposite pinnately veined leaves. (A plant-name used 

 by Pliny and meaning heJonging to the god Mercury.) 



1. M. Annua L. Weak erect leafy-stemmed annual ; leaves lanceolate or 

 ovate-lanceolate, crenate-serrate ; carpels hispid, — Waste places and ballast 

 ground, N. S. to S. C. and O. (Adv. from Eu.) 



6. ACAL'S'PHA L. Three-seeded Mercury 



Flowers monoecious ; the sterile very small, clustered in spikes ; the few or 

 solitary fertile flowers at the base of the same spikes, or sometimes in separate 

 ones. Calyx of the sterile flowers 4-parted and valvate in bud ; of the fertile, 

 3-5-parted. Corolla none. Stamens 8-16 ; filament short, monadelphous at 

 base ; anther-cells separate, long, often worm-shaped, hanging from the apex 

 of the filament. Styles 3, the upper face or stigmas cut-fringed (usually red). 

 Capsule separating into 3 globular 2-valved carpels, rarely of only one carpel. — 

 Herbs (ours annuals), or in the tropics often shrubs, resembling Nettles or 

 Amaranths ; the leaves alternate, petioled, with stipules. Clusters of sterile 

 flowers with a minute bract ; the fertile surrounded by a large and leaf-like 

 cut-lobed persistent bract. ('A/ca\r/077, an ancient name of the Nettle.) 



* Fruit smooth or merely pubescent; seeds nearly smooth. 



1. A. virginica L. Smoothish or hairy, .3-6 dm. high, often turning purple ; 

 leaves ovate or oblong-ovate, obtusely and sparsely serrate, long-petioled ; 

 sterile spike rather few-flowered, mostly shorter than the large leaf-like pal- 

 mately 5-9-cleft fruiting bracts; fertile flowers 1-3 in each axil. — Fields 

 and open places, N. S. to Out. and Minn., s. to the Gulf. July-Sept. 



2. A. gracilens Gray. Finely pubescent and often villous ; leaves lanceolate 

 or even linear, less toothed and shorter-petioled ; the slender sterile spike 

 often 2 cm. long, and much sin-passing the less cleft or few-toothed fruiting 

 bracts. (A. virginica, var. Muell. Arg.) — Sandy or dry soil, s. N. H. to Fla. . 

 w. to e. Kan. and Tex. — Carpels by abortion sometimes reduced to one (A. 

 monococca Engelm.). 



* * Fruit echinate with soft bristly green projections ; seeds rough-wrinkled. 



3. A. ostryaefblia Riddell. Leaves thin, ovate-cordate, sharply and closely 

 serrate-toothed, abruptly acuminate, long-petioled ; sterile spikes short, axillary ; 

 the fertile ones mostly terminal and elongated, their bracts deeply cut into 

 many linear lobes. (A. caroliniana Ell., not Walt.) — N. J. to Fla.. w. to O., 

 Kan., and Tex. 



