72 CRUCIFER^E. (MUSTARD FAMILY.) 



2. S. candscens, Nutt. (TANSY MUSTARD.) Leaves ^-pinnatifid , often 

 hoary or downy, the divisions small and toothed; flowers yellowish, very 

 small; pods in long racemes, oblong-club-shaped or oblong-linear, shorter 

 than their mostly horizontal pedicels; seeds 2-ranked in each cell. Penn 

 and N. Y. to Lake Superior, thence southward and westward. June - Aug. 



S. SOPHIA, L. A similar hoary species, with decompound leaves; pods 

 slender, 6-15" long, ascending; seeds 1-ranked. Sparingly naturalized 

 from Europe. 



S. OFFICINALE, Scop. (HEDGE MUSTARD.) Leaves runcinctte ; flowers 

 very small, pale yellow ; pods awl-shaped, dose pressed to the stem, scarcely 

 stalked. Waste" places. May - Sept. An unsightly branched weed, 2-3 

 high. (Nat. from Eu.) 



S. THALIANA, Gaud. (MOUSE-EAR CRESS.) Leaves obovate or oblong, entire 

 or barely toothed ; flowers white ; pods linear, somewhat 4-sided, longer than 

 the slender spreading pedicels. Old fields and rocks, Mass, to Kan. April, 

 May. A span high, slender, branched, hairy at the base. (Nat. from Eu.) 



S. ALLIARIA, Scop. Stout, erect ; leaves reniform to ovate-cordate, coarsely 

 repand-dentate ; flowers white ; pods tapering, 1-2' long, ascending on very 

 stout spreading pedicels. Near Georgetown, D. C. (Nat from Eu.) 



16. THELYPODIUM, Endl. 



Pod terete or teretish ; valves 1 -nerved ; stigma mostly entire. Seeds in 1 

 row in each cell, oblong, marginless. Cotyledons obliquely incumbent. 

 Stout biennials or perennials, with mostly large purplish or white flowers. 

 Leaves or petioles often auricled at base. (Name from 0r)Avs, female, and 

 trovs,foot, the ovary in some species being stipitate.) 



1. T. pinnatifidum, Watson. Glabrous (1-3 high), often branched 

 above; root-leaves round or heart-shaped, on slender petioles; stem-leaves 

 auricled, ovate-oblong and ovate-lanceolate (2-6' long), sharply and often 

 doubly toothed, tapering to each end, the lower into a winged petiole, rarely 

 bearing a pair or two of small lateral lobes; flowers purplish; pods 1-H' 

 long, on short diverging pedicels, pointed by a short style. (Arabis hesperid- 

 oides, Graii.) Alluvial river-banks, W. Pa. to Minn., Mo., and southwestward. 

 May, June. 



17. BBASSICA (Brassica and Sinapis), Tourn. 



Pod linear or oblong, nearly terete or 4-sided, with a stout 1 -seeded beak or 

 a rigid style; valves 1-5-uervecl. Seeds globose, 1 -rowed. Cotyledons 

 incumbent, folded around the radicle. Annuals or biennials, with yellow 

 flowers. Lower leaves mostly lyrate, incised, or pinnatifid. (The Latin name 

 of the Cabbage. Sinapis is the Greek (rivairi, which is said to come from the 

 Celtic nap, a turnip.) 



B. SiNApf STRUM, Boiss. (or SIN\PIS ARVENSIS, L., the English CHARLOCK), 



^with knotty pods, fully one third occupied by a stout 2-edged beak (which it 



either empty or 1 -seeded), the upper leaves barely toothed, is a noxious 



weed in grain-fields, from N. Eng. to Penn. and N. Y. westward. (Adv. from 



Eu.) 



B. (or SINAPIS) ALBA. (WHITE MUSTARD.) Pods bristly, ascending on 

 spreading pedicels, more than half its length occupied by the sword-shaped 1- 

 seeded beak ; leaves all pinnatifid ; seeds pale. (Cult, and adv. from Eu.) 



B. (or SIX\PIS) NIGRA, Koch. (BLACK MUSTARD.) Pods smooth (' long), 

 4-cornered (the valves only 1-nerved), erect on appressed pedicels forming a 

 slender raceme, tipped with a stout persistent style ; seeds dark brown, smaller 



