230 Rhodora [SEPTEMBER 
Drummondi only in its much wider pods (mostly 3 mm. wide). A 
plant quite like it in habit and with similarly broad pods is repre- 
sented in the Gray Herbarium by several Rocky Mountain specimens, 
one of which, Hall & Harbour’s no. 35, was apparently a source of 
some perplexity to Dr. Gray, who first referred to it as Streptanthus 
augustifolius ‘and later took it to be Zwrritus brachycarpa “a short- 
fruited form of 7: stricta, Graham.” ? Other similar specimens from 
Colorado (as Patterson’s of 1875) ‘and from Washington (Hender- 
son's no. 2397) have passed as true 4. Drummond, while a recent 
Colorado collection (Baker's no. 341) has been made the type of a 
proposed new species, 4. connexa, Greene. As an extreme of A. 
Drummondi this plant seems very well marked, but with the same 
habit and pubescence, and with only the inconstant tendency to 
broader pods, it seems better treated as a variety of that widely dis- 
tributed plant. 
The three eastern plants which have been associated as Aradis 
Drummondi and the ill-defined A. confinis may be briefly distinguished, 
then, as follows. 
* Basal leaves glabrous or with some simple centrally attached hairs: pods 
erect or strongly ascending. 
A. DnuMMONDI, Gray. Biennial, usually slightly glaucous, gla- 
brous throughout (except for the occasionally pubescent basal leaves), 
2 to 9 dm. high: basal leaves oblanceolate, slender-petioled, entire 
or dentate; cauline erect or strongly ascending, oblong- to linear-lan- 
ceolate, entire, sagittate-clasping: flowers pink or whitish, 7 to 1o mm. 
long, on slender erect pedicels: pods erect (except in age), straight 
or slightly curved, normally flat, 3.5 to ro cm. long, 1.3 to 2.3 mm. 
broad, bluntly pointed: seeds in 2 irregular rows, short-oblong to 
broadly elliptical, winged.— Proc. Am. Acad. vi. (1866) 187. 
A. Drummondii Gray, Man. ed. 5, 69, in part; Watson, Syn. Fl. i 
pt. 1, 166, in part. 4. /aevigata, Hook. Fl. Bor.-Am. i. 43 (1829), not 
Poir. A. confinis, Watson, Proc. Am. Acad. xxii. (1887) 466 ; Wats. 
Syn. Fl.l. c. 163; in part; Watson & Coulter, in Gray, Man. ed. 
6,67,in part. A. brachycarpa, Britton, Mem. Torr. Cl. v. (1894) 174, 
Ill. Fl. ii. 150 and Man. 464; in part. A. oxyphylla, Greene, Pittonia, 
iv. (1900) 196.  Zurritis stricta, Graham, Edinb. New Phil. Jour. 
1829, 350; Hook. l. c. 40; Torr. & Gray, Fl. i. 79; Torr. Fl. N. Y. i. 
53; Gray, Gen. Ill. i. 144, t. 59; not Arabis stricta, Huds. — 7: glabra, 
B., Torr. & Gray, l. c. 78, 666. Streptanthus angustifolius, Nutt. in 
! Gray, Proc. Acad. Phila. 1865, 57. 
? Gray, Proc. Am. Acad. vi. 187. 
