CRUCIFER2E. (MUSTARD FAMILY.) 69 



brous in the following species, except the base of the stem and the lower or tuft of 

 radical leaves, these mostly hirsute. ) 



10. A. perfoliata, Lam. (TOWER MUSTARD.) Tall (2 -4 high); 

 glaucous ; stem-leaves oblong or ovate-lanceolate, entire, half-clasping by the 

 sagittate base ; petals yellowish-white, little longer than the calyx ; pods very narrow 

 (3' long) and pedicles strictly erect. (Turritis glabra, L.) Rocks and fields, 

 scarce and perhaps introduced southward ; more common northward. (Eu.) 



11. A. Drummondii, Gray. Scarcely glaucous, l-2 high; stem- 

 leaves lanceolate or oblong-linear and sagittate (!' -2' long) with jiarrow auricles, 

 or the lowest spatulate ; petals white or rose-color, fully twice the length of the calyx; 

 pedicels and flat pods loosely erect, or ascending, or even spreading ; seeds wing- 

 margined, when mature little narrower than the partition. (Turritis stricta, 

 Graham.) Rocky places, from the St. Lawrence in Canada East, to Lewiston 

 (Clinton), Lake Superior, and northwestward; also " Chenango Co. New 

 York," Northern Illinois, Vasey. Pods 2^' -3' long, or invar. (T. brachy- 

 carpa, Tver. $- Gray) only l'-2' long. 



6 . B A R B A R E A , R. Br. WINTER CRESS. 



Pod linear, terete or somewhat 4-sided ; the valves being keeled by a mid- 

 nerve. Seeds in a single row in each cell, marginless. Cotyledons accumbent. 

 Mostly biennials resembling Nasturtium ; flowers yellow. (Anciently called 

 The Herb of St. Barbara.') 



1. B. VUlgaris, R. BR. (COMMON WINTER CRESS. YELLOW ROCKET.) 

 Smooth ; lower leaves lyrate, the terminal division round and usually large, the 

 lateral 1-4 pairs or rarely wanting ; upper leaves obovate, cut-toothed, or pin- 

 natifid at the base ; pods erect or slightly spreading ; or in var. STRICTA, ap- 

 pressed ; in var. ARCU\TA, ascending on spreading pedicels. Low grounds 

 and roadsides : apparently introduced, but indigenous from L. Superior north- 

 ward and westward. (Eu.) 



2. B. PR^COX, R. BR. (EARLY WINTER C.), with 5-8 pairs of lateral lobes 

 to the leaves, and longer pods on very thick pedicels, yet probably only a vari- 

 ety of the other, somewhat cultivated from New York southward as a winter 

 salad, under the name of SCURVY-GRASS, is beginning to run wild. (Eu.) 



7. ERYSIMUM, L. TREACLE MUSTARD. 



Pod linear, 4-sided ; the valves keeled with a strong midrib. Seeds in a sin- 

 gle row in each cell, oblong, marginless. Cotyledons (often obliquely) incum- 

 bent. Calyx erect. Chiefly biennials, with yellow flowers ; the leaves not 

 clasping. (Name from f'pu'o), to draw blisters.) 



1. E. cheiranthoides, L. (WORM-SEED MUSTARD.) Minutely rough- 

 ish, branching, slender ; leaves lanceolate, scarcely toothed ; flowers small ; pods 

 small and short (7"- 12" long), very obtusely angled, ascending on slender di- 

 vergent pedicels. Banks of streams, New York, Penn., Illinois, and northward. 

 July. (Eu.) 



2. E. asperum, DC., var. Arkansanum, Nutt. (WESTERN WALL- 

 FLOWER.) Minutely roughish-hoary ; stem simple; leaves lanceolate, some- 



