208 
IOWA ACADEMY OF SCIENCES. 
214. R. ohtusifolius L. Waste ground; rare. 
215. E. persicarioides L. Damp fields and along 
streams; scarce. 
Fagopyrum . 
216. F. fagopyy'um (L.) Karst. {F. escidentmn Moench,) 
Waste ground; infrequent and not long per- 
sistent . 
Polygonum. 
217. P. dmphihium L. Ponds and swamps; frequent. 
218. P. hartwrightii Gray. Low ground; infrequent. 
219. P. enter sum (Michx.) Brit. (P. muhlenbergii 
Wats.) In swamps and along streams; common. 
220. P. incarnatum Ell. (P. lapathifolium incarnatum 
Wats.) Damp fields and waste ground; common. 
221. P . pennsylvanicum L. Abundant in moist, culti- 
vated ground . 
222. P. persicaria L. Abundant in fields and waste 
ground. 
228. P. hydropiper L. Abundant in swampy ground 
and wet fields. 
224. P. punctatuni Ell. (P. acre H. B. K.) With the 
preceding, but less abundant.' 
225. P. orientale L. Barely escaped. 
226. P. virginianum L. Frequent in damp, shady 
ground. 
227. P. aviculare L. Abundant about houses and in 
waste ground. 
228. P. erectum L. Common in waste ground. 
229. P.tenue Michx. Dry, sterile ground; scarce, 
280. P. convolvulus L. Abundant in fields and waste 
ground. • 
231. PI scandens L. (P. dumetorum scandens Gray.) 
Thickets and low river banks; common. 
CHENOPODIACE^. 
Chenopodium. 
232. C. album L. Cultivated and waste groilnd; 
abundant. 
