RYDBERG: Rocky MouNTAIN FLORA 431 
Streptanthus wyomingensis A. Nelson but probably rather a Zhely- 
podium.” This note made the writer compare the latter species. 
When S. wyomingensis was first described, it was thought that it 
was the closest ‘relative of S. maculatus Nutt., the only original 
Streptanthus, but a closer comparison now has shown that the pod 
is not flat as in Streptanthus and the lobes of the stigma are turned 
the wrong way. Its relationship is with the three 7) helypodia just 
mentioned above, with which it also agrees in habit. 
Two other species of 7helypodium are said by Dr. Robinson 
to have the lobes of the stigma placed in the same way, viz.: 7. 
micranthum and T. longifolium, but here that character is scarcely 
noticeable. There are other characters in which they disagree 
with the other Zhelypodia. The branched or stellate pubescence 
is unique in the whole tribe and should place them according to 
the classification used in Engler & Prantl’s Pflanzenfamilien in 
another grand division of the family. The stamens and the pods 
are, however, more or less thelypodioid. In both species the 
flowers are more or less irregular, the lower sepals being longer 
(this is best shown in 7 longifolium) and there is scarcely any 
distinction between claw and blade in the petals. 
The most interesting of the Thelypodia is perhaps 7. Wrightii. 
In the pod, the texture of sepals and petals, the form of the latter, 
etc., this is close to the typical 7helypodia. The habit is not so 
essentially different either, but the sepals are spreading-reflexed 
and early deciduous as in Stanleya and the glands at the base of 
the stamens and the thickening of the pedicel, both so conspicu- 
ous in most thelypodioid plants, are here inconspicuous. The 
plant could not be included in Stanleya, on account of the short 
stipe, the different habit and the structure of the petals. 
The genera may be distinguished as follows : 
Sepals equal or nearly so; hairs simple or none. 
Sepals erect or ascending in anthesis. 
Stigma distinctly lobed, its lobes expanded over the septum. 
Thelypodiopsis. 
Stigma entire or, if indistinctly lobed, the lobes expanded over the valves. 
Stigma truncate ; sepals scarcely gibbous at the base. 
Septum of the pod without a distinct midrib. Thelypodium. 
Septum of the pod with a strong midrib. Pleurophragma. 
Stigma conical; the outer sepals gibbous at the base. Hesperidanthus. 
Sepals strongly spreading or reflexed in anthesis, soon deciduous. 
Stanleyella. 
