132 XANTHOXYLACEyE. Zanthoxylum. 



Order XXX. XANTHOXYLACEtE. Ad. Juss. The Prickly-ash Tribe. 



Flowers by abortion dioscious or polygamous, regular. Calyx of 3 - 5 sepals. 

 Petals as many as the sepals, or rarely none, convolutely imbricated in sestiva- 

 tion. Stamens as many as the sepals and alternate with them, or twice as 

 many, arising from the base of the torus which bears the abortive carpels. 

 Ovaries usually equal in number to the sepals, sometimes fewer, inserted on the 

 convex or elevated torus, distinct or more or less united, each with 2 (rarely 4) 

 ovules. Styles united into one when the ovaries are combined ; usually distinct, 

 or partly so, when the ovaries are not connate. Fruit sometimes baccate or 

 membranaceous, sometimes composed of 1 - 5 drupes or 2-valved capsules ; 

 the rather fleshy sarcocarp partly separable from the endocarp. Seeds one 

 or two in each cell or carpel, anatropous, pendulous, with a crustaceous testa, 

 usually smooth and shining. Embryo lying within fleshy albumen : cotyledons 

 oval, flat. — Trees or shrubs, aromatic, pungent and bitter. Leaves without 

 stipules, simple or pinnate, usually marked with pellucid dots. 



1. ZANTHOXYLUM. L. ; H. B. 4- K. nov, gen. ^ spec. Q,.p.\; Endl. gen. 597&. 



PRICKLY ASR 



[ From the Greek, xanthos, yellow, and xyhn, wood.] 



Flowers polygamo-dioecious. Sepals 3-5, small. Petals longer than the sepals, or none. 

 Stamens as many as the sepals and opposite them (or fewer) ; those of the pistillate flower 

 rudimentary. Ovaries 1-5, raised on a globose or cylindrical torus, distinct or united at 

 the base, with 2 collateral suspended ovules : styles distinct or united at the apex, some- 

 times very short. Carpels sessile or stipitate on the torus ; crustaceous in fruit, 1-2- 

 seeded. Seeds oval-globose when solitary, hemispherical when in pairs, black and shining. 

 — Trees or shrubs, usually with strong prickles. Leaves usually pinnate, rarely simple or 

 trifoliolate. Flowers small, greenish or whitish. 



^ Zanthoxylum proper, Colden. Sepals 5, with a minute glandular bexrd at the apex : petals 

 none. : ovaries as many as the sepals and opposite them : styles at first somewhat united : stigmas 

 clavate. 



1. Zanthoxylum Americanum, 3Iill. Common Prickly Ash 



Branches, and often the petioles, armed with short strong (stipular) prickles ; leaves pin- 

 nate ; leaflets ovate-oblong, nearly sessile, obscurely serrfclate or entire, more or less pubescent; 

 flowers in short axillary sessile umbels; carpels stipilalc. — Willd. beschr. (1781), p. IIG; 



