IOWA ACADEMY OF SCIENCES. 
231 
Strophostyles Ell. 
349. S. helvola (L.) Britton. ( S . augulosa Ell; Phaseolus 
diver sifolius Pers.) River banks near Arm- 
strong; rare. 
350. S. pauciflora (Benth. ) S. Watson. ( Phaseolus 
pauciflorus Benth.) Sandy shore of Swan Lake; 
rare. 
OX ALLDACE,®. 
Oxalis L. 
351. 0. violacea' L. Violet Wood-sorrel. Woods and 
prairies; very common. 
352. 0. stricta L. (0. corniculata var. stricta Sav.) Yel- 
low Wood-sorrel. Very common. 
LINACE^E. 
Linum L. 
353. L. sulcatum Riddell. Wild Eiax. Frequent on 
dry prairies. 
354. L. usitatissimum L. Flax. Escaped from cultiva- 
tion to roadsides, where it persists for a year or 
two. 
RUTACE^E. 
Xanthoxylum L. 
355. X. americanum Mill. Prickly Ash. 
shrub, frequent in woods. 
A prickly 
POLYGALACE^E. 
POLPGALA L. 
356. P. verticillata L. Frequent on low prairies. 
357. P. viridescens L. (P. sanguinea L.) Very rare; 
prairies near Armstrong. 
EUPHORBIACEYE. 
Acalypha L. 
358. A. virginica L. Common in the woods south; of 
Iowa Lake. 
