132 BRASSICACEAE. 



1. BURSA Weber. Annual herbs. Leaves sometimes mainly basal: blades 

 entire to pinnatifid. Racemes terminal. Sepals 4, spreading. Petals 4, much 

 longer than the sepals. Ovules and seeds many in each carpel. Pods euneate. 



1. B. Bursa-pastoris (L.) Britton. Stems 3-9 dm. tall: basal leaves 3-15 cm. 

 long; blades mainly pinnately lobed or pinnatifid; blades of the stem-leaves 

 auricled at the base: pedicels 10-15 mm. long: sepals 1.5-1.7 mm. long: petals 

 white, spatulate, 2-2.3 mm. long : pods 5-8 mm. long. Common, in fields and 

 waste places. Nat. of Eu. -Spr.-fall. SHEPHERD 'S-PURSE. 



2. LEPIDITJM [Tourn.] L. Annual, biennial, or perennial herbs. Leaf- 

 blades entire to pinnatifid. Racemes terminal. Sepals 4, spreading. Petals 4, 

 longer than the sepals or wanting. Stamens usually fewer than 6. Ovule, and 

 seed, 1 in each carpel. Pods suborbicular to oblong. Spr. and sum. 



Blades of the cauline leaves sagittate-clasping : pods winged. 1. L. campestre. 

 Blades of the cauline leaves tapering at the base : pods wingless, 



margined. 2. L. virginicum. 



1. L. campestre (L.) E. Br. Plants 1-4 dm. tall, softly fine-pubescent: blades 

 of the lower leaves spatulate to oblanceolate, those of the upper leaves sagit- 

 tate, clasping, shallowly toothed: pedicels downy: sepals oblong to oblong- 

 ovate, about 1.5 mm. long: petals white, spatulate, 2-2.5 mm. long: pods 

 ovoid, 4.5-5.5 mm. long, winged above the base, minutely pubescent. Rather 

 common, in fields and on roadsides. Nat. of Eu. COW-CRESS. FIELD-CRESS. 



2. L. virginicum L. Stems 2-9 dm. tall, puberulent: blades of the cauline 

 leaves narrow, sharply toothed or incised: pedicels spreading, 3^ mm. long at 

 maturity: sepals oblong, about 1 mm. long: petals slightly larger than the 

 sepals : pods 3-4 mm. long. Common, in waste places and fields. PEPPER- 

 GRASS. 



3. TKLASPI [Tourn.] L. Annual or perennial erect or depressed caules- 

 cent herbs. Leaf -blades entire or toothed, those of the upper leaves auriculate- 

 clasping. Racemes inconspicuously bracted or bractless, elongating. Sepals 

 rather broad. Petals white or purplish, longer than the sepals, equal or nearly 

 so. Filaments stout: anthers short. Pods orbicular, obovate or euneate, 

 winged, notched at the apex. 



1. T. arvense L. Annual, 1-5 dm. tall, glabrous: blades of the lower cauline 

 leaves of a spatulate type, those of the upper cauline leaves sagittate, 1.5-5 

 cm. long, toothed: sepals oblong or oblong-ovate, 2-2.5 mm. long: petals white, 

 euneate to spatulate, 2.5-3 mm. long: pods suborbicular to orbicular-obovate, 

 1-1.5 cm. broad, broadly winged. M. S. Not common, in waste places and 

 on roadsides. Nat. of Eu. Spr. and sum. PENNY-CRESS. 



4. CAMELINA Crantz. Annual herbs. Leaf -blades entire or toothed, or 

 pinnatifid at the base of the stem, sometimes clasping. Racemes elongate. 

 Sepals 4, rather broad. Petals 4, narrow, yellowish or greenish. Stamens 6: 

 anthers ovoid. Style columnar. Ovules few or many. Pods turgid, margined. 

 Seeds marginless. Spr. FALSE-FLAX. 



Stem manifestly pubescent : pods rounded at the apex, 4-5 mm. wide. 



1. C. microcarpa. 

 Stem glabrous or nearly so : pods truncate or notched at the 



apex, 6-8 mm. wide. 2. C. sativa. 



1. C. microcarpa Andrz. Plants pubescent, at least below, 5-8 dm. tall: 

 blades of the upper cauline leaves lanceolate, 1.5-7 cm. long, sagittate-auricu- 

 late at the base: pods narrowly obovoid, 4-5 mm. wide: seeds fully 1 mm. 

 long. S. Rather common, in fields. Nat. of Eu. 



