1. Platanus occidentalis L. Fig. 491. 



Large tree to 50 m. tall and with a trunk to 4 m. in diameter; bark mottled 

 brown and white or buff due to exfoliation; leaves broadly ovate to suborbicular 

 or broadly reniform in outline, to about 2 dm. in diameter, truncate to cordate 

 at base, essentially glabrous or with stellate pubescence on lower surface, 3- or 

 5-lobed, usually with broadly rounded shallow sinuses; leaf lobes mostly broadly 

 triangular and acuminate, entire or with few long remote pointed teeth; fruiting 

 heads 25 mm. or more in diameter, usually persistent on the tree during at least 

 part of winter; fruit narrowly clavate, about 8 mm. long; seed brownish, about 6 

 mm. long. Incl. var. glabrata (Fern.) Sarg. and f. attenuata Sarg. 



Mostly along streams and in bottomlands in s.e. Okla. and throughout most of 

 Tex. e. of Val Verde Co., Mar.-May; from Me., w. to Ont. and Neb., s. to n. Fla. 

 and Tex. 



2. Platanus Wrightii Wats. Arizona sycamore. Fig. 491. 



Large tree to 24 m. high, with arched white-barked branches spreading to 

 form a broad crown; trunk and branches with the outer bark flaking off to expose 

 the smooth whitish inner bark; buds enclosed in the dilated bases of the petioles; 

 leaves large, to about 3 dm. in diameter, alternate, palmately lobed; flowers 

 numerous in dense globose heads; sepals and petals minute; pistils 3 or 4, dis- 

 tinct; fruit a 4-sided achene, with a basal tuft of long hairs. P. racemosa Nutt. var. 

 Wrightii (Wats.) L.Benson. 



Along streams and in low wettish areas, rather widespread in southw. N.M. 

 and the s. half of Ariz., Apr .-May; also n. Mex. 



Fam. 73. Rosaceae Juss. Rose Family 



Trees, shrubs or herbs; leaves alternate, simple or compound; stipules present, 

 sometimes caducous to obsolete or wanting; flowers mostly perfect, regular 

 or nearly so, having a floral cup ("hypanthium") formed by the fusion of the 

 bases of sepals, petals and stamens (this appearing in some taxa with inferior 

 ovaries to be merely the outer layer of the ovary wall); sepals usually 5, some- 

 times 3 to 8, rarely united at base, often appearing double by a row of outer 

 bractlets; petals as many as the sepals, rarely wanting or numerous by "doubling," 

 mostly imbricated in the bud and usually inserted with the stamens on the edge 

 of the floral cup; stamens usually numerous, inserted near the edge of the floral 

 cup; pistils one to many, distinct or united and sometimes adnate to the floral 

 cup or hypanthium; ovules 1 to several in each carpel; endosperm scanty or 

 absent; fruit a follicle, achene, pome or more or less aggregate drupelets or an 

 achenelet. 



This diverse family of plants perhaps comprise more than 2,000 species in 

 about 100 genera. They are represented in most areas of the world but are most 

 abundant in eastern Asia, North America and Europe. Its production of miscel- 

 laneous fruits edible to man is not surpassed by any other family of plants; 

 among these are the apple, peach, pear, cherry, apricot, plum, almond, strawberry, 

 raspberry and blackberry. Its contribution to ornamentals, epitomized by the rose, 

 is of the highest importance. Many species provide food and forage for domestic 

 and wildlife. 



1. Annual or perennial herbs above ground, unarmed, the caudex often some- 

 what woody (2) 



1. Hardy or perennial shrubs or trees, if somewhat herbaceous then provided with 

 prickles (6) 



1015 



