RUMEX.] TOLYGONAGEJE. 351 



brown. Panicle with erect branches, leafless ; male whorls densely 4-8-fld. ; 

 pedicels jointed below the middle. Sepals of male fl. herbaceous, margins 

 white or pink, scarious ; of female, in. when in fruit, piuk or crimson, 

 Fruit brown, shining. DISTRIB. N. temp, and Arctic zones. A salad snd 

 pot-herb ; abounds in binoxalate of potash. 



11. R. Acetosella, L. ; dioecious, lower leaves hastate, uppermost 



sessile, outer fruiting sepals appressed, inner hardly enlarged oblong- 



ovate entire herbaceous, midrib thickened at the base. Sheepi's Sorrel. 



Dry pastures, N. to Shetland, ascends to 2,500 ft. in York ; Ireland ; Channel 



Islands; fl. May-Aug. Perennial, acid, glabrous, often bright red in autumn. 



Rootstock creeping, much branched. Stems 3-20 in., often many and tufted, 



decumbent at the base, slender. Leaves |-2 in., long-petioled, variable in 



breadth, often 3-lobed; stipules silvery, torn. Panicle leafless, branches 



erect ; male flowers largest ; pedicels as long as the fruiting sepals, jointed 



at the top, length variable. Fruiting sepals r \ in., obtuse, closely investing 



the yellow-brown fruit. DISTRIB. N. temp, and Arctic zones ; introd. into 



theS. 



3. OXYR'IA, Hill. MOUNTAIN SORREL. 



Characters of Rumex, but sepals 4 ; anthers versatile ; ovary com- 

 pressed ; stigmas 2 ; fruit lenticular, broadly winged, and embryo axile. 

 DISTRIB. Arctic regions and Alps of the N. temp, zone ; species 1. 

 ETYM. ou's, from the acidity of the leaves. 



O. digyna, Hill ; leaves cordate or reniforin. 0. renifor'mis, Hk. 

 Mountain rocks and streams, from N. Wales and Westmoreland to Orkney ; 

 ascends to near 4,000 ft. ; S.W. Ireland ; fl. July-Aug. Perennial, glabrous, 

 rather fleshy, acid. Rootstock tufted. Stem 6-18 in., stout, subsimple. 

 Leaves, radical many, |-f in. broad, long-petioled, rounded or retuse, rarely 



orbicular-cordate, membranous, veined, top notched. An excellent pot-herb 

 and antiscorbutic. 



OliDEft LXIJI. ARISTOLOCHIA'CE.ffi. 



Herbs or shrubs, often climbing. Leaves alternate, entire or lobed, 

 exstipulate. Flowers 2-sexual, solitary spiked or racemed, regular or 

 irregular. Perianth superior, tubular, campanulate or trumpet-shaped ; 

 limb 3-lobed or 1 -lipped, valvate in bud. Stamens 6 or 12, rarely 5 ; 

 anthers subsessile, free or adnate to the style, cells introrse or extrorse. 

 Ovary 4-6-celled ; styles 6, inner surface stigmatic ; ovules very many, 

 anatropous, 2-seriate in the inner angles of the cells. Fruit a 4-6-valved 

 septicidal capsule, or a berry. Seeds horizontal flattened or boat-shaped, 

 raphe thickened, albumen copious fleshy or horny ; embryo minute, 



