MUSTARD FAMILY 253 



6. STREPTANTHELLA Rydb. Fl. Rocky Mts. 364. 1917. 



Glabrous, annual herbs with entire or shallowly dentate leaves and branched stems. 

 Flowers small. Pods pendent on recurved pedicels ; stipe none ; valves strongly com- 

 pressed, narrowed at the apex to a conspicuous beak that simulates a persistent style, 

 dehiscent at the base but remaining attached at the apex. Seeds flattened, narrowly 

 winged ; cotyledons oblique. [Greek, diminutive of Streptanthus.'] 



A monotypic genus of western United States and northwestern Mexico. 



1. Streptanthella longirostris (S. Wats.) Rydb. Streptanthella. Fig. 1955. 



Arabis longirostris S. Wats. Bot. King Expl. 17. pi. 2. 1871. 

 Streptanthus longirostris S. Wats. Proc. Amer. Acad. 25: 127. 1889. 

 Guillenia rostrata Greene, Leaflets Bot. Obs. 1 : 228. 1906. 

 Streptanthella longirostris Rydb. Fl. Rocky Mts. 364. 1917. 

 Thelypodium longirostris Jepson, Man. Fl. PI. Calif. 413. 1925. 



Stem usually much branched above, slender, 3-6 dm. high. Leaves deciduous at maturity; 

 lower stem leaves narrowly oblanceolate, sinuate-dentate or repand, 2-5 cm. long ; upper leaves 

 reduced, entire; sepals greenish or tipped with purple, 3-6 mm. long, lateral pair saccate at 

 base; petals yellowish, linear-spatulate, one-fourth longer than sepals; inflorescence lax, shortly 

 racemose, elongating in fruit ; pedicels soon recurved, slender, 2-5 mm. long ; pods 3-7 cm. long, 

 1-2 mm. wide; stigma nearly entire. 



Upper and Lower Sonoran Zones; eastern Washington and eastern Oregon south to the Mojave Desert, 

 including the arid Inner Coast Ranges of Fresno and Monterey Counties, California, east to Wyoming, Arizona, 

 and adjacent Mexico. Type locality: Steamboat Springs, Nevada. March-June. 



Streptanthella longirostris yar. derelicta J. T. Howell, Leaflets West. Bot. 2: 57. 1937. Leaves at 

 least all but the upper pinnatifid into a few narrow divaricate lobes. Colorado Desert, southern California and 

 adjacent Arizona, Lower California and Sonora, Mexico. Type locality: on sand hills near La Quinta, River- 

 side County, California. 



7. CAULANTHUS S. Wats. Bot. King Expl. 27. 1871. 



Mostly annual herbs, frequently glabrous and glaucous or sometimes pubescent with 

 simple hairs. Basal leaves usually not forming a conspicuous rosette. Flowers purple, 

 white, or yellow, racemose. Sepals equal or quite unequal. Petals frequently narrow and 

 crisped. Pods erect, divaricate or reflexed, terete or only slightly flattened, often torulose, 

 sessile or nearly so; style usually short; stigma entire or 2-lobed with the lobes extended 

 over the middle of the valves; cells of the septum usually short and the boundaries 

 straight. Cotyledons usually obliquely incumbent. [From the two Greek words meaning 

 stem and flower, in allusion to cauliflower, since some of the species may be used as a 

 substitute for cabbage.] 



A genus of about 18 species, native to the arid regions of western North America. Type species, Caulan- 

 thus crassicaulis (Torr.) S. Wats. 



Stem leaves sessile, auriculate at the base. 

 Stems not distinctly inflated. 



Stigmas entire or shallowly 2-lobed. 



Plants glabrous or inconspicuously short-pubescent. 



Pods erect or divaricate. 1. C. amplexicaulis. 



Pods reflexed. 2. C. Cooperi. 



Plants hirsute; stigma very small, entire. 3. C. stenocarpus. 



Stigma distinctly 2-lobed. 



Pods 2-4 cm. long; cotyledons 3-parted. 4. C. calif ornicus. 



Pods 4-14 cm. long; cotyledons not 3-parted. 

 Pods usually reflexed. 



Calyx yellowish; stigma distinctly but not deeply 2-lobed. 5. C. simulans. 



Calyx purple; stigma deeply 2-lobed. 6. C. Coulteri. 



Pods erect, 8-13 cm. long. 7. C. Lemmonii. 



Stems conspicuously inflated. 8. C. inftatus. 



Stem leaves sessile or petioled, not auriculate at base. 

 Stems more or less inflated. 



Stigma shallowly 2-lobed; calyx glabrous. 9. C. major. 



Stigma deeply 2-lobed; calyx hispid, rarely glabrous in crassicaulis. 



Annual; leaves more or less hispid. 10. C. Hallii. 



Short-lived perennial; leaves glabrous. 11. C. crassicaulis. 



Stems not inflated. (See also C. major.) 



Plants glabrous; annual. 12. C. glaucus. 



Plants densely pilose. 13. C. pilosus. 



1. Caulanthus amplexicaulis S. Wats. Clasping-leaved Caulanthus. Fig. 1956. 



Caulanthus amplexicaulis S. Wats. Proc. Amer. Acad. 17: 364. 1882. 

 Pleiocardia magna Greene, Leaflets Bot. Obs. 1 : 87. 1904. 

 Euclisia amplexicaulis Greene, Leaflets Bot. Obs. 1: 84. 1904. 

 Streptanthus amplexicaulis Jepson, Man. Fl. PI. Calif. 417. 1925. 



Annual, glabrous throughout, more or less glaucous, the stem slender, somewhat flexuous, 



