STUDIES IN THE CRUCIFER®. 189 
A. RHODANTHA, Greene, Pitt. iii, 155. While differing 
from A. Holbollii very markedly in its long loose raceme of 
small rose-red flowers, as well as in its short-pedicelled re- 
fracted pods, this Colorado plant has no simple hairs, its 
stem, glabrous above, exhibits only the usual very fine 
stellate pubescence on its lower part. As a species, it is 
about equally removed from the two preceding; and the 
three are near allies. 
A. SECUNDA, Howell, Eryth. iii, 33. An excellent species, 
with better characters than Mr. Howell assigned. The stel- 
late pubescence is both more scanty and more soft than in 
any of the foregoing, and is nowhere more pronounced than 
on the pedicels, and it recurs, though sparingly, on the per- 
fectly mature pods; and the valves of these are singularly 
almost carinate-nerved, while between this midnerve and 
the margins the space is occupied by a system of narrow 
almost linear reticulation, or series of interrupted striations, 
as the lines might perhaps better be called. 
‘A. TENUIS. Perennial, the younger plants simple and 
with a simple raceme, the older with branched and ligne- 
scent but slender caudex; flowering stem and raceme 
mostly about a foot high, very slender, erect and strict: 
lowest leaves oblanceolate, petiolate, entire, the whole about 
i inch long, both faces finely stellate-canescent, the indu- 
ment extending to stem and cauline leaves, and even to 
pedicels, calyx and growing ovary: cauline leaves linear, 
broadest at the slightly auricled base: flowers very small, 
the spatulate white or pinkish petals about twice the length 
of the sepals: pods very narrowly linear, about 2 inches 
long, straight, closely deflexed on short and slender pedicels, 
obtuse or acutish: seeds uniserial, orbicular, wingless, 
though with a slight scarious margin. 
