1921] 
PAYSON—MONOGRAPH OF THE GENUS LESQUERELLA 221 
ton 7160 (Rky. Mt. Herb. and U. S. Nat. Herb.); Panguitch 
Lake, Sept. 6, 1894, Jones 6002e (U. S. Nat. Herb.); canyon 
above Tropie, May 28, 1894, Jones 5312d (U. S. Nat. Herb.). 
L. utahensis is perhaps the most interesting of all the species 
of Lesquerella because of the great similarity, in some of its forms 
particularly, to members of the genus Physaria. So striking, 
indeed, is this similarity that one is a little perplexed at times 
to know to which genus a given plant should be referred. And 
yet utahensis as a species is not entirely satisfactory, so close is 
it to other forms that give no suggestion of Physaria. The 
bridge connecting the two genera is nearly complete. 
L. utahensis, as here limited, is rather polymorphic and when 
more adequate collections are at hand it may be capable of 
resolution into several geographic varieties. This species seems 
most closely related to Wardii but that species has, when ma- 
ture, large, irregularly ellipsoid pods. Both are conspicuous 
rosette formers. L. Kingii is perhaps more difficult to separate 
from utahensis than is Wardii. It has a more southern and 
western range, the stems are longer and more nearly erect, and 
the pods more densely pubescent. L. prostrata differs from the 
present species in the somewhat elongated pods and the acute, 
frequently subhastate leaves. 
48. L. prostrata A. Nelson, Bull. Torr. Bot. Club 26: 124. 
1899; Nelson in Coulter & Nelson, Manual Cent. Rocky Moun- 
tains,219. 1909; Rydb. 
Fl. Rocky Mountains, 
332. 1917. 
Perennial, silvery stel- 
late-pubescent through- 
out, stellae many-rayed, $7 
rays forked near the 
base, distinct; stems 
prostrate or ascending, 
unbranched, 6-15 cm. Fig. 32. L. prostrata. Habit sketch x L4. Tri- 
long; terminal bud re- "mes x T 
maining undeveloped; radical leaves ovate or subhastate, obtuse 
or acute, usually distinctly angular, 1-3.5 cm. long, blade abruptly 
narrowed to the slender petiole which usually exceeds it in length; 
