158 ANACARDIACE^. 



Fruit a small and dry or nut-like drupe, smooth, granu- 

 lated, or hairy ; the sarcocarp thin and juiceless ; the endo- 

 carp bony or crustaceous, smooth or striate. Seed conformed 

 to the cell, which it fills, amphitropous, commonly transverse, 

 somewhat reniform, the hilum superior ; testa membrana- 

 ceous or thickish. Albumen none. Embryo filling the seed : 

 COTYLEDONS oval or oblong, flat, nearly foliaceous, usually 

 transverse : radicle short, lying on the side next the fu- 

 niculus, superior, incurved or uncinate and lying against 

 the edge of the cotyledons (cotyledons accumbent); in R. 

 Cotinus, where the apex of the fruit becomes lateral from 

 unequal development, the radicle is descending. 



Trees or shrubs, sometimes climbing by rootlets, yielding 

 a resinous, or sometimes viscous-milky, often caustic juice. 

 Leaves alternate, pinnate with a terminal leaflet, or pinnate- 

 ly trifoliolate, rarely simple, destitute of stipules, commonly 

 deciduous. Flowers small, white or greenish, in axillary or 

 terminal panicles, often thyrsoid, rarely in catkin-like spikes, 

 more commonly dioecious than monoecious. 



Etymology. The ancient Greek and Latin name of tlie genus. 

 Geographical Distribution. This rather large and polymorphous 

 genus is widely distributed over the temperate and subtropical regions of the 

 world, but is most abundant in North America, Japan, and at the Cape of 

 Good Hope. A few species are tropical. Ten species are known within 

 the United States proper; and one other abounds in Oregon and California, 

 where it takes the place of our R. Toxicodendron. The Californian Rhus 

 (Malosma) laurina. Nut/., belongs to the originally Chilian genus Lithrcea, 

 of Miers. 



Division. The following subgenera are represented in the United States, 

 viz. : — 



§ 1. Cotinus, Tourn. — Flowers perfect. Drupes semi-obcordate, gla- 

 brous, veiny, the apex brought down on one side ; the radicle therefore 

 descending (as in Geranium). — Leaves simple. Panicles ample and 

 loose, most of the pedicels abortive and becoming much elongated, plu- 

 mose-villous. (To this section belongs R. Cotinus, the Venetian Su- 

 mach or Smoke-tree of our gardens, and the closely allied R. cotinoides, 

 Niitt., which Mr. Buckley found in Alabama.) 

 § 2. Sumac, DC. (excl. spec.) — Flowers more or less polygamous, in a 

 terminal thyrsoid panicle. Drupes ovoid or globular, red or crimson, 



