APETALOUS EXOGENOUS PLANTS. 467 



Sub-order II. Eriogoneae. Flowers surrounded by 

 an involucre. Calyx G-parted. Stamens 9. Ovule sessile. 

 Emhryo included in scarce albumen. Stipules none. 



Involucre toothed. Woolly or silky herbs EaiOGONUM. 



RUMEX, L. Dock. 



Flowers perfect or dioecious ; calyx herbaceous, 6-parted, 

 the 3 outer lobes spreading or recurved, the inner ones 

 (valves) mostly enlarged in fruit, and inclosing the 3-an- 

 gled achenium, often bearing grain-like prominences on the 

 outside; stamens 6; anthers erect; styles Z', stig7nas many - 

 cleft ; aclienium 3-angled ; embryo curved on the outside of 

 the albumen. — Herhs, with alternate leaves, smooth trun- 

 cated sheaths, and small green fioiuers in racemed or pani- 

 cled clusters. 



* Flowers perfect or polygamous. 

 t Valves entire. 



R. CRISPUS, L. Smooth ; leaves lanceolate, wavy-crisped? 

 acute at both ends, or the lowest truncate or slightly cor- 

 date at the base, and long-petioled, the uppermost linear ; 

 panicle leafy at the base ; whorls crowded in fruit ; valves 

 broadly cordate, obtuse, one or all grain-bearing. Waste 

 ground around dwellings. June and July. Stem 2°-3° 

 high ; lowest leaves 1° long. Perennial. 



R. Floridanus, Meisner. Smooth ; stem stout, branch- 

 ing ; leaves lanceolate, acute at each end ; panicle naked, 

 dense-flowered; pedicels about twice as long as the valves, 

 thickened upward, reflex ed in fruit; valves deltoid-ovate, 

 obtusely pointed, each bearing a narrow grain, which is 

 much narrower than the reticulate valve. Deep river- 

 SAvamps. June. Stem 2°-3° high ; leaves i°-l J° long. 



tt Valves toothed or bristly on the margins. 



R. MARITIMUS, L. Pubescent; ste7n low, diffusely 

 branched ; leaves lanceolate, wavy-margined, the lower ones 



