IOWA ACADEMY OF SCIENCES 
35 
Saxix. 
224. S', nigra Marsh. Scarce. 
225. S. omygdaloides Anders. 
226. S. lucida Muhl. 
227. S. alM, viteUina (L) Koch. Escaped from cultivation. 
228. S. cordata Muhl. Plenty in marshy places. 
229. S. fluviatilis Nutt. Abundant along streams. 
230. 8. discolor Muhl. In marshy places. 
231. 8. humilis Marsh. Common on open prairie. 
232. S. tristis Ait. In dry rocky woods. 
233. 8. Candida Fluegge. 
JUGLANDACEAE. 
JUGEANS. 
234. J. nig7'a L. Comparatively scarce in woods. 
235. J. cinerea L. Much more common. 
Hicoria. 
236. H. ovata (Mill.) Britton. Common in woods. 
237. H. laciniosa (Michxf.) Sarg. Scarce in woods. 
238. H. glalora (Mill.) Britton. Abundant in woods. 
BETULACEAE. 
Carptnus. 
239. C. caroliniana Walt. Plenty in wmods. 
OSTRYA. 
240. 0. virginiaiia (Mill.) Willd. Abundant in woods. 
COKYLUS. 
241. G. americana Walt. Abundant in woods. 
FAGACEAE. 
Quercus. 
242. Q. rubra L. Plenty in woods. 
243. Q. palustris DuRci. Scarce. In marshy woods. 
244. Q. sclinechii Britton. Scarce. 
245. Q. coccinca Wang. Plenty. 
246. Q. borealis Michx. Scarce in woods. 
247. Q. velutina Lam. Common in woods. 
248. Q. alba L. Common in woods. 
249. Q. macrocarpa Michx. Abundant in woods. 
250. Q. platanoides (Lam.) Sudw. Scarce. 
ULMACEAE. 
Ulmus. 
251. U. americana L. Abundant. 
252. TJ. racemosa Thomas. Not so common as above. 
253. TJ. fulva Michx. Abundant in 'woods. 
Celtts. 
2^4. C. occidentalis L. Plenty in woods. 
