IOWA ACADEMY OF SCIENCES. 
221 
Euphorbia. 
402. E. glyptosperma Eng. Dry, open grounds; fre- 
quent . 
403. E. maculdta L. Abundant in waste ground. 
404. E . nutans Lag. (E. prestii Grurs.). Dry, sterile 
ground; abundant. 
405. E. corollata L. Sandy fields and waste ground; 
frequent. 
406. E. mar ginata PuYsh . Rarely an escape. 
407. E. Jieterophylla L. Stony, waste ground; infre- 
quent. 
408. E . peplus L. Waste ground; rare. 
409. E . cyparissias L. Rarely escaped . 
ANACARDIACE^ 
Rhus. 
410. R. glabra L. Thickets and borders of woods; com- 
mon • 
411. R. radicansh, (R. toxicodendron h . ?) Woods 
thickets and roadsides; common. 
CELASTRACE^. 
Euonymus. 
412. E . atropurpureus J£icq. Frequent in woods. 
Celastrus. 
413. C. scandens L. Woods and thickets; common. 
, STAPHYLEACE^. 
Staphylea. 
414. 8 . trifolia h . Woods frequent. 
Acer. 
415. 
416. 
417. 
ACERACE^. 
A. saccharinum L. (A. dasycarpum Ehrh.) 
Along streams; frequent. 
A. saccharum Marsh. (4. saccharinum Wang.) 
High woods; common. 
A. negundo L. {Negundo aceroides Moench.) 
Borders of woods; common. 
