TETRADYNAMIA— SILICULOSA. Thlaspi. 171 



Bursa Pastoris. Toiirn. t. 103. 

 Capsella. DeCand. Syst. v. 2. 383. 



Cal. equal at the base, with ovate, concave, moderately 

 spreading, deciduous leaves. Pet. obovate, equal, undi- 

 vided, sometimes slightly notched ; their claws short and 

 broad. Filam. simple, slender. Anth. heart-shaped, acute. 

 Germ, roundish, compi-essed, notched. Style short. Stig- 

 ma obtuse. Pouch transversely compressed, roundish or 

 inversely heart-shaped, crowned between its lobes with 

 the style, of 2 cells ; valves strongly keeled, mostly bor- 

 dered ; partition elliptic-lanceolate, crossing the greater 

 diameter of the pouch. Seeds several in each cell, ovate; 

 cotyledons accumbent. 



Perennial or annual herbs, for the most part smooth, with 

 undivided, rarely pinnatifid, leaves. Fl. white. Pouches 

 variously shaped and bordered. 



1. T. arvense. Mithridate Mustard, or Penny Cress. 



Pouch orbicular, nearly flat, shorter than its stalk. Leaves 

 smooth, oblong, toothed. Stem erect. 



T. arvense. Linn. Sp. PL 901. mild. v. 3. 442. H. Br. 683. 



Engl. Bot. V. 24. t. 1659. Curt. Lond. fasc. 6. t. 43. Hook. 



Scot. 1 93. DeCand. Syst. v. 2. 375'. Fl. Dan. t. 793. 

 T. Dioscoridis. Rail Sijn. 305. Ger. Em. 262. f. 

 T. secundum. 3Iatth. Falgr. v. 1.519. /. Camcr. Epit. 337. /. 



Dalech. Hist. 662./. 

 T. cum siliquis latis. Bauh. Hist. v. 2. 923./". 

 Nasturtium n. 5 1 1 . Hall. Hist. v. 1 . 220. 

 Penny Cress. Petiv. H. Brit. f. 50./. 9. 



In cultivated or waste ground, but not common. 



In Essex, Suffolk, and Staffordshire. Ray. Oxfordshire. Bishop 

 of Carlisle. In waste ground on the north-east side of Norwich. 

 Mr. Rose. Near the sea at the south end of Lowestoft, Suffolk. 



Annual. June, July. 



Root small and tapering. Herb deep shining green, quite smooth, 

 erect, 8 to 12 inches high, branched, leafy. Radical leaves obo- 

 vate, obtuse ; those of the stem oblong, acute, arrow-shaped and 

 clasping at the base ; all toothed, or wavy. Fl. small, white, 

 densely corymbose. Pouches very large, erect, in long clusters, 

 orbicular, with a deep notch at the top, the broad borders of 

 their valves rising high above the style. Seeds striated, black, 

 acrid, with a strong garlic flavour, which occasioned them to be 

 used formerly as an ingredient in the Mithridate Confection, an 

 elaborate hodge-podge, now laid aside. The name of Penny 

 Cress alludes to the form and size of the seed-vessels, resembling 

 a silver penny. 



