MUSTARD FAMILY 329 



7. T. purpurascens Rydb. Stems generally several, less than 1 dm. high; 

 basal leaves oval or broadly spatulate, 2-3 cm. long, petioled, usually more or 

 less sinuate-dentate; stem-leaves ovate, obtuse, with a truncate base, closely 

 sessile; petals about 6 mm. long; pod triangular-obovate, distinctly winged above, 

 7-8 mm. long. Alpine peaks: Colo. — Utah — Ariz.^ — -N.M. Subalp. — Alp. 

 My-Jl. 



5. BURSA Weber. Shepherd's Purse. 



Annual caulescent herbs, pubescent with branched hairs. Leaves alternate) 

 entire, lobed, or pinn'atifid. Flowers perfect, in elongate racemes. Petals 

 white, spatulate. Stamens free and unappendaged. Styles almost none; 

 stigma simple. Pod strongly flattened contrary to the narrow septum, cuneate 

 or obcordate, more or less deeply notched at the apex, the valves boat-shaped. 

 Seeds numerous in each cavity, marginless. Cotyledons accimibent. 



1. B. Bursa-pastoris (L.) Britton. Annual or winter biennial; stem 1-5 

 dm. high; lower leaves usually iyrate-pinnatifid, lobed or merely dentate; stem- 

 leaves sessile, hastate or sagittate at the base; petals white, 2 mm. long, spatu- 

 late; pods 6-8 mm. long, triangular. Capsella Bursa-pastoris Medic. Waste 

 places: Lab. — Fla. — Calif. — -B.C.; S. Am.; nat. from Eurasia. Plain — Subalp. 

 Ja-D. 



6. HUTCHINSIA R. Br. 



Low spreading annuals, minutely stellate or glabrous. Leaves alternate, 

 entire to pinnately lobed. Flowers perfect, in at last elongate racemes. Stigma 

 sessile. Petals minute, narrow, white. Pods strongly' flattened contrary to 

 the narrow septum, elliptic, not at all obcordate or notched at the apex. Seeds 

 numerous in each cell. Cotyledons accumbent. 



1. H. procumbens (L.) Dev. Stems branched at the base, slender, 

 5-20 cm. long; lower leaves pinnatifid, lobed, toothed, or entire, minutely stellate; 

 upper leaves entire, oblanceolate or linear; sepals and petals about 1 mm. long; 

 fruiting pedicels divaricate; pod elliptic, about 4 mm. long. Moist ground: 

 Lab. — Newf. — Colo. — Calif.— B.C. Plain — Submont. Mr-Je. 



7. SMELOWSKIA C. A. Meyer. 



Low cespitose perennials, with a suffruticose caudex and cinereous stellate 

 pinnatifid leaves. Flowers perfect, racemose. Sepals subequal, somewhat 

 spreading. Petals obovate, exserted, white or ochroleucous or tinged with 

 purple. Pod lanceolate or ovate, more or less obcompressed; valves strongly 

 keeled. Stigma sessile. 



Basal leaves merely lobed, cuneate to oblanceolate in outline; pod 5-6 mm. long, tapering 



towards the base. 1. S. lobala. 



Leaves aU deeply pinnatifid. 



Pod ovate, 4-.5 mm. long, obtuse at the base; calyces and pedicels densely villous; 



leaves white-villous. 2. S. ovalis. 



Pod lanceolate or oblanceolate, 7-12 mm. long, tapering at each end. 



Segments of tlie basal leaves spatulate or oblong. 3. S. americana. 



Segments of the basal leaves Linear or Unear-oblong. 4. S. lineariloba. 



1. S. lobata Rydb. Stems 1 dm. or less high; stem-leaves pinnatifid; sepals 

 densely villous, 3 mm. long, ovate, acute; petals white, clawed, rounded-obovate; 

 pod glabrous, about 5-6 mm. long, oblanceolate; style very short. High moun- 

 tains: Alta. — -Mont. Subalp. Je-Jl. 



2. S. ovalis M. E. Jones. Stems about 1 dm. high, densely white-villous 

 and stellate; basal leaves floccose-stellate, pinnately divided into 5-7 oblong, 

 entire, or 2-3-cleft divisions; petals clawed, with rounded-obovate blades; pods 

 obtuse at the base. High mountains: Wash. — Alta. — Calif. Mont. — Subalp. 

 Jl-Au. 



3. S, americana Rydb. Stems 1-2 dm. high; leaves finely but not densely 

 stellate; petals long-clawed, spatulate; pod 7-12 mm. long, tapering at both 

 ends. High mountains: Mont. — ^Colo. — Utah — Ida. Mont. — Alp. Je-Jl. 



4. S. lineariloba Rydb. Stems about 1 cm. high, few-leaved; leaves 2-5 

 cm. long, finely stellate, the petioles also ciliate; petals clawed, 5-6 mm. long, 



