BVckeve Family. 31 



bluffs; April; a frequent tree along the water courses of eastern and south- 

 ern Iowa, extending far into the interior. Allamakee to Lee county, thence 

 west as far as Decatur county. (A. saccharinum Wang 1 .) 



A. nigrum Mx. Similar to the preceding; leaves green both sides, pube- 

 scent beneath at least on the veins, lobes shorter, broader, but little undulate 

 or often entire, sinuses very obtuse, the basal one nearly closed. With the 

 preceeding; Fayette, Story, Decatur and Emmet counties; infrequent or rare; 

 often put as var. n'mrwm T. & (x. of the preceeding. 



A. rubrum L. Red or Swamp M. Twigs reddish; leaves 3-5-lobed, lobes 

 serrate, acuminate, green above, pale or whitish beneath, sinuses acute, base 

 cordate; flowers reddish or yellowish, short pedicelled; petals linear-oblong; 

 fruiting pedicels elongated. Low grounds along river; rare; Johnson 

 county. 



A. spicatum Lam. Mountain It. A shrub or small tree; leaves 3-5-lobed, 

 glabrous above, pubescent beneath, coarsely serrate, lobes acuminate; flow- 

 ers in a dense erect compound raceme, greenish yellow, appearing after the 

 leaves; petals linear-spatulate; samaras small somewhat divergent. Muffs of 

 the Mississippi river; Allamakee, Clayton, and Dubuque eounties: rather 

 rare. 



* * Leaves pinnate; flowers dioecious. 



A. negundo L. Box Elder. Ash-leaved M. Tree of average size; leaflets 3- 

 5, ovate or oval, pubesceut when young, becoming glabrous, acute, dentate or 

 entire; flowers dioecious, appearing shortly before the leaves, drooping, 

 small, apetalous; samaras glabrous somewhat incurved. Low woods; April; 

 common. (Netjundo aevroides Moench ) 



HIPPOCASTANACEAE T. & G. Buckeye Family. 



Trees or shrubs, with opposite petioled digitately 5-7-foliate leaves, 

 and irregular polygamous paniculate flowers. Calyx tubular, 5-toothed. 

 Petals 4-5, unequal, clawed. Stamens 7, filaments slender, unequal. 

 Ovary 3-celled, with 2 ovules in each cell. Fruit coriaceous, 3-celled, 3- 

 valyed, 3-seeded or by abortion 1-celled, 1-seeded. Represented by the 

 genus Aesculus L. 



AE. glabra Willd. Ohio Buckeye. Tree 10-40 feet high, bark fetid; leave's 

 long-petioled; leaflets 5, ovate to lanceolate, acuminate, finely serrate; flow- 

 ers in terminal thyrsoid panicles, pale yellow: petals 4; stamens curved, ex- 

 serted; fruit globular, covered with prickles; seed large, shining, red; scar 

 large, roundish, pale. Alluvial soil and rich uplands; May; frequent; Des 

 Moines, Lee, Henry, Van Buren, Jefferson, Johnson, Boone, Polk, Appanoose, 

 Decatur, Ringgold, .Union, and Taylor counties. 



AE. octandra Marsh. Sweet B. Flowers yellow; petals 4, conniving, 

 long-clawed; stamens included; fruit smooth. May; Jasper county, reported 

 by Prof. Shimek; apparently infrequent. (AE. flava Ait.) 



STAPHYLEACEAE DC. Bladder-nut Family. 



Ours a small shrub, with 3-foliate stipulate leaves, and axillary droop- 

 ing racemose flowers. Sepals, petals, and stamens 5. Styles 3. Pod 

 large, membranous, inflated, 3-lobed, 3-celled, separating above, each cell 

 with 1-4 bony seeds. Represented by the genus Staphylea L. 



S. trifolia L. Amei-ican Bladder-nut. Shrub 4-12 feet high; flowers white 

 Moist woods; May; frequent throughout. 



