HITCHCOCK — PLANTS OF AMES, IOWA. 507 



OLE ACE. E. 



Fbaxinus Americana, L. Spec. 2d ed. 

 Upland woods. 



This species is apparently rare. Although diligently searched for, only one tree 

 was found near the railroad, north of the brick-kiln. It is easily recognized by its 

 cylindrical fruit with the wing not decurrent, and by its rather slender-pctiolcd leaf- 

 lets being whitened beneath. 



F. viridis, Michx. f. Hist. Arb. Am. iii. 1813. 

 Woods ; abundant. 



A small or medium sized tree, growing in both upland and lowland woods ; leaf- 

 lets mostly 5, oval to narrowly lanceolate, sharply serrate, or neatly entire, gla- 

 brous or with more or less pubescence along the veins beneath, tapering into a 

 somewhat margined petiole; fruit with slender striate body, tapering to an acute 

 base, and decurrent obovate oblong or lanceolate rctuse or acute wing 1 to 3 times 

 the length of the body. 



Var. pubescens. 



Upland woods ; Ames; Hamilton count}-, Fremont county, Sioux 



City. 

 This differs from F. viridis in having the twigs of the season densely pubescent. 



F. sambucifolia, Lam. Diet. ii. 



Along streams ; infrequent. 



A medium sized tree with oblong spray, dark green foliage, and close bark, 

 becoming mottled with white as in the Black Maple; leaflets sessile, 7 to 11. Oc- 

 curs along the clay bluffs of Skunk river, mostly near the water but often on the 

 sides or top; also sparingly on Clear creek about one mile west of the College, on 

 Onion creek, and in a few other localities. 



APOCTNACEsE. 



A'POCYNUM ANDROS.EMIFOLIUM, L. Spec. 

 Rich open woods ; frequent. 



A. CANNABINUM, L. Spec. 

 Moist banks ; abundant. 



AS CLE PI A DA CE.E. 



ASCLEPIAS TUBEROSA, L. Spec. 

 Prairie; abundant. 



Yar. decumbens, (L.) Pursh, Fl. — Asclepias decumbens, L 



Spec. 

 Sterile soil ; infrequent. 

 A. purpurascens, L. Spec. 



Prairie and open woods; not uncommon. 

 A. INCARNATA, L. SpeC. 



Low ground ; common. 

 A. Byriaca, L. Spec.— A. Comuti, Decaisne in DC. Prod. vili. 



Fields, pastures, and open woods; abundant. 

 A. BuiiLIVANTil, Engel. in Gray Man. 1st. ed. 



Low prairie; frequent. 



