Platanus. PLATANACE^. 219 



branches whitish ; fertile heads solitary. — Linn. sp. 2. p. 999 ; Michx. fi. 2. p. 1 63 ; Michx. 

 sylv. 1. «. 63 ; Pursh, fi. 2. p. 635 ; Ell. sk. 2. p. 620 ; Bigel. fl. Bost. p. 358 ; Beck, hot. 

 p. 327; Darlingt. fl. Cest. p. 542; Loud. enc. tr. <^ shr.p. 931. 



A very large tree, often 60 - 80 feet high and 2-5 feet or more in diameter, with thick 

 spreading branches. The bark separates in thin hard plates, leaving a whitish surface under- 

 neath. Leaves roundish in the outline, longer than broad, 4-8 inches wide, truncate or 

 cordate at the base, clothed with a deciduous pubescence : teeth acuminate : petioles 1-3 

 inches long, pubescent when young, smoothish when old. Stipules sheathing, with a spread- 

 ing leafy toothed border. Sterile heads in small globose beads, deciduous. Fertile heads 

 consisting of numerous naked pistils aggregated on a globose receptacle : ovary oblong, taper- 

 ing into a long subulate style. Fruiting ament about an inch in diameter, forming a compact 

 ball, which hangs on a tough slender peduncle 3-4 inches long, and remains through the 

 winter. Nuts slender, clavate, tapering to the base, and clothed with numerous long tawny 

 hairs. 



Banks of rivers ; common in nearly all parts of the State. Fl. May. Fr. September. 

 The wood of this well known shade tree is little used either for timber or fuel. It is liable 

 to warp, and soon decays in moist places. It is said, that many years ago, a Button-wood tree 

 grew in the western part of this State (I think on the Genesee river), the trunk of which was 

 more than fifteen feet in diameter. 



Order CV. URTICACEtE. DC. The Nettle Tribk. 



Flowers monoecious, dioecious or polygamous, sometimes collected in aments or 

 fleshy heads, furnished with a regular calyx, but destitute of corolla. Stamens 

 definite : anthers curved inward in sestivation. Ovary free from the calyx, 

 simple, one-celled with a solitary ovule, or very rarely 2-celled and an ovule in 

 each cell. Fruit an achenium or utricle, often enclosed in a fleshy or baccate 

 calyx. — Trees or shrubs with a milky juice, or herbs with a watery juice, often 

 stinging. Leaves often stipulate. 



Suborder I. MOREiE. Endl. The Mulberry Tribe. 



Staminate and pistillate flowers in separate spikes or aments, which finally be- 

 come succulent, forming a compound fruit ; or intermixed and enclosed in the 

 same hollow and fleshy receptacle. Seeds albuminous. — Mostly trees or shrubs 



with a milky juice. 



28* 



