REVISION OF RUMEX. 83 



middle ; valves 5 to 8 mm. in diameter, orbicular 

 or broader than long, conspicuously cordate, erose or 

 obtusely low dentate below, round or bluntly short acu- 

 minate at apex; callosities solitary (exceptionally wanting 

 or a second or third developed), globose, smooth, rarely 1 

 mm. long; achene 2x3.5 ram. Sp. i. (1753), 333; Meis- 

 ner, DC. Prod. xiv. 51. Introduced along roadsides and 

 in fields at various points in the Atlantic States, from 

 Europe, where it is cultivated for its acid foliage ; possibly 

 escaped from German kitchen gardens in its American 

 stations. Specimens examined from Saskatchewan ( Ma- 

 coun, 1872, 1030), Ontario (Macoun, 1874), Ver- 

 mont (Jesup, 1873), Massachusetts (Hitchcock, 1829; 

 Tuckerman; Jesup), New York (Howe; Brown, 1879, on 

 ballast),New Jersey ( Schre.nJc, 1879, and Martindale, 1880, 

 on ballast), Pennsylvania (Martindale, 1882), Wisconsin 

 ( Trelease, 1887), Iowa (Hitchcock), Kansas (Kellerman), 

 and Utah (Jordan Valley, Watson, 1869, 1050), the 

 last named locality quite out of the usual range, but the 

 plants scarcely anything else. Plate 20. 



9. K. BRITANNICA, L. Three or four feet high, erect, 

 stout, at length considerably branched ; leaves glabrous, 

 little undulate, ample or the lowest very large, elliptical to 

 ovate lanceolate, decurrently rounded or commonly acute 

 at base, the apex very gradually pointed; panicle few 

 leaved, ample, rather dense in fruit ; whorls rather dense, 

 remote but at length overlapping; pedicels about twice as 

 long as the fruit, very obscurely and not tumidly jointed 

 toward the base; valves 4x4.5 to 5x6 mm., round ovate, 

 scarcely cordate, remotely erose or low-denticulate, obtuse, 

 their lower veins sometimes much thickened at base ; callosi- 

 ties 3, subequal, broad and low, sometimes wrinkled on the 

 sides, more than half as long ; achene 1.7x3. 5mm. Sp. i. 

 (1753), 334; Gray. Proc. Amer. Acad. viii. 399. .K. 

 orbiculatus, Gray, various editions of the Manual. Swamps, 

 New Brunswick to the Lakes, south to New Jersey, Illinois, 



