BRASSICACEAE 485 



Flowers perfect, in elongating racemes. Sepals 4, narrow, early deciduous. Corolla yel- 

 low or yellowish, the 4 petals slightly longer than the sepals. Ovary sessile : style short : 

 stigma minute. Ovules numerous. Pods linear or narrowly oblong, flattish, the valves 

 1-nerved. Seeds in 1 or 2 rows in each cavity. Cotyledons incumbent. TANSY MUS- 

 TARD. The plants flower mainly in the spring and summer. 



Pods narrowly linear, 1.5-2.5 cm. long, 1 mm. wide, curved upward. 1. S. Sophia. 



Pods oblong or linear-oblong, 5-14 mm. long, 1-2 mm. wide, straight or nearly so. 



Foliage densely canescent : pedicels horizontal : pods ascending. 2. S. pinnata. 



Foliage glabrate or sparingly canescent. 



Pedicels and pods horizontal. 3. S. mittefolia. 



Pedicels ascending : pods nearly erect. 



Pods mostly shorter than the pedicels. 4. S. intermedia. 



Pods mostly longer than the pedicels. 5. S. brevipes. 



1. Sophia Sophia (L. ) Britton. Foliage minutely hoary-canescent. Stems 3-7.5 

 dm. tall, usually much branched : leaves 3-14 cm. long ; blades 2-3-pinnatifid into nar- 

 rowly linear or oblong-linear segments : flowers numerous : pedicels slender, 12-16 mm. 

 long, ascending, glabrous or nearly so : pods narrowly linear, 1.5-2.5 cm. long, curved up- 

 ward : seeds in 1 row in each cavity. 



In waste places, New Brunswick to Ontario, Nebraska, New York and about the northern sea-ports. 

 Naturalized from Europe. FLAX WEED. 



2. Sophia pinnata ( Walt. ) Britton. Annual, canescent with pale hairs and sometimes 

 glandular. Stems erect, 2-6 dm. tall, simple, or branched above, the branches ascending : 

 leaves with short petioles and 2-pinnatifid blades, the segments oblong : racemes elongating, 

 sometimes paniculate : pedicels slender, spreading, 8-15 mm. long : sepals oblong, about 

 1 mm. long : petals spatulate, equalling or somewhat surpassing the sepals : pedicels hori- 

 zontal, 10-14 mm. long: pods oblong, straight, 6-8 mm. long, glabrous, ascending: seeds 

 in 2 rows in each cavity. [Sisymbrium canescens Nutt. ] 



In dry soil, Virginia to Florida and Texas. 



3. Sophia millefolia Rydb. Bather taller and less leafy than S. pinnata and nearly 

 glabrous. Leaves 2-9 cm. long ; blades oval or oblong-oval in outline, very thin, less 

 dissected : pedicels 12-20 mm. long: pods club-shaped, less than 1 cm. long, with a very 

 short style : seeds in 2 rows in each cavity. [S. myriophylla Rydb., not Sisymbrium 

 myriophyllum DC.] 



In dry soil, Kentucky to Texas. 



4. Sophia intermedia Rydb. Annual, nearly glabrous or thinly stellate-pubescent 

 and glandular. Stems erect, 2-7 dm. tall, more or less branched above : leaves with short 

 petioles and pinnate or bipinnatifid blades : segments linear or oblong : racemes elongating, 

 simple or branched : pedicels filiform, 10-20 mm. long, widely ascending : sepals oblong, 

 1-2 cm. long at maturity : petals sometimes nearly twice as long as the sepals : pods linear- 

 oblong, straight, 8-15 mm. long, acute, glabrous or nearly so, erect or nearly so : seeds in 

 1 row in each cavity. 



In dry soil, Minnesota to the Northwest Territory, British Columbia, Tennessee, Texas and Cali- 

 fornia. 



5. Sophia brevipes (Nutt.) Rydb. Foliage minutely canescent or puberulent. 

 Stems 5-6 dm. tall : leaves 2-7 cm. long ; blades pinnately divided into 5-7 segments, these 

 pinnatifid, with obtuse lobes : pedicels erect-appressed, 3-8 mm. long, mostly shorter than 

 the pods : pods erect or nearly so, linear, 8-10 mm. long, about 1 mm. wide : seeds in 1 

 row in each cavity. [Sisymbrium canescens brevipes Nutt. ] 



In dry soil, Minnesota to British Columbia and Texas. 



25. STREFTANTHUS Nutt. 



Annual or biennial caulescent herbs, with often glaucous foliage. Leaves alternate : 

 blades entire or toothed or rarely pinnatifid, the cauline sagittate and clasping at the base. 

 Flowers perfect, in terminal racemes. Calyx not campanulate. Sepals often purplish, 

 barely saccate at the base. Petals purple or white or rarely yellowish, with narrow claws 

 and broad well developed blades. Stamens 6 : filaments of the longer pairs sometimes 

 united below : anthers sagittate. Ovary sessile on the enlarged receptacle. Ovules several 

 or numerous. Pods oblong to narrowly linear, flattened. Seeds flattened, margined or 

 winged. Cotyledons accumbent. 



Flower-stalks with conspicuous scales. 1. S. bracteatus. 

 Flower-stalks without scales or these minute. 



Pedicels naked : pods 10-13.5 cm. long, 2 mm. wide. 2. S. maculatus. 



Pedicels often with minute scales : pods 5-7.5 cm long, 4-5 mm. wide. 3. S. platycarpus. 



