178 



NORTH AMERICAN FLORA 



[Volume 25 



commonly grooved and sometimes winged, unarmed or armed with straight or curved 

 mostly slender brownish prickles. Inflorescence terminal or axillary, cymose, paniculate, 

 racemose, spicate, glomerate, or rarely 1-flowered. Flowers white, yellowish-white, or green- 

 ish-white, dioecious or polygamous. Calyx hypogynous, sometimes wanting ; sepals 3-5, 

 commonly more or less united. Petals 3-10. Stamens 3-5, hypogynous, alternate with 

 the petals, rudimentary or wanting in the pistillate flowers ; filaments filiform or subulate ; 

 anthers elliptic to nearly orbicular or ovate. Pistils 1-5, raised on a fleshy gynophore, 

 sometimes slightly united below, rudimentary in the staminate flowers. Ovaries 1-celled ; 

 styles short and slender, more or less united toward the summit ; stigmas capitate ; ovules 

 2 in each cavity, collateral, pendulous from the inner angle of the cell. Follicles 1-5 ; 

 endocarp free. Seeds oblong, ovoid, or globose, suspended on a slender funiculus, often 

 hanging from the carpel at maturity ; seed-coat black or reddish, shining ; embryo straight or 

 curved; cotyledons oval or orbicular, foliaceous. 

 Type species, Zanthoxylum Clava-Hcrculis L. 



essile, axillary cymes ; petals 4 or 5 ; gynoecium 



A. .Sepals wanting. 

 Flowers in small, 



2-5-carpellary. 1. Z. wmericanum, 



Flowers in terminal panicles ; petals9orl0; gynoecium 1-carpellary. 2. Z.ferrugineum. 



B. Sepals present and in most species long-persistent in fruit. 



a. Sepals, petals, and stamens 3 (rarely 4 in a few flowers of the same 

 inflorescence). 

 Inflorescence congested, scattered in the axils of the leaves, or 

 rarely terminal on the same branches, usually few-flowered, 

 0.5-1.5 cm. long. 

 Gynoecium 1-carpellary ; lateral veins of leaflets few, compara- 

 tively distant ; follicles solitary. 

 Follicles 3-4 mm. long, 3-4 mm. broad ; seeds 2.2-3 mm. long, 

 2-3 mm. broad ; marginal glands of the leaflets small, distant, 

 and not forming a conspicuous row. 3. Z. tacdiosum. 



Follicles 4.5-6 mm. long, 4.5-5.5 mm. broad ; seeds 3.5-4.8 

 mm. long, 3^4 mm. broad ; marginal glands of the leaflets 

 large, close together, and forming a conspicuous row. 41 Z. Shaferi. 



Gynoecium 2- or 3-carpellary ; lateral veins of leaflets numerous, 

 close together ; follicles 2 or 3, sometimes 1 or 2 abortive. 

 Gynoecium 2-carpellary ; follicles 3.5-4.5 mm. long; leaflets 



2-8 cm. long, 1-4 cm. broad. 5. Z. punciatum. 



Gynoecium 3-carpellary ; follicles 7-8 mm. long ; leaflets 

 "1.5-2.5 cm. long, 1.3-2 cm. broad. 6. Z. ihomasianum 



Inflorescence terminal or lateral in the axils of the upper leaves, 

 commonly many-flowered, 1.5-15 cm. long. 

 Gynoecium 1-carpellary ; follicles solitary. 



Leaves equally pinnate; leafletsacumiuate,commonlybroadest 

 at or below the middle. 

 Follicles 4-4.8 mm. long, 3-4.5 mm. broad, blackish ; mar- 

 ginal glands of the leaflets obsolete. 

 Follicles 5-7 mm. long, 4.6-6 mm. broad, brown ; mar- 

 ginal glands of the young leaflets conspicuous. 

 Inflorescence 3-7 cm. long, rather few-flowered ; lateral 



veins of leaflets 1-2 mm. distant. 8. Z. acuminatum. 



Inflorescence 9-15 cm. long, very many-flowered; lateral 

 veins of leaflets 4-12 mm. distant. 

 Leaves odd-pinnate ; leaflets obtusely short-acuminate, 

 rounded or emarginate, broadest above the middle. 

 Gynoecium 3-carpellary ; follicles 3, sometimes 1 or 2 abortive. 

 Leaflets 11-25, commonly 13-19, ovate to orbicular, 0.8-2 cm. 



long, 0.5-1.8 cm. broad, obtusely short-acuminate. 11. Z. pimpint lloides. 



Leaflets 4-13, commonly 5-10, oblong to oval or obovate, 

 usually over 2 cm. long. 

 Leaves normally odd-pinnate, often crenulate. 



Leaves 3.5-10 cm. long ; leaflets rounded or obtuse, 1.5- 



4.3 cm. long, 0.8-2.8 cm. broad. 

 Leaves 13-24 cm . long; leaflets usually obtusely short- 

 acuminate, 2.8-11 cm. long, 1.5-4.8 cm. broad. 

 Leaves normally equally pinnate, usually entire. 

 Leaflets obovate. 



Leaflets elliptic to ovate or nearly orbicular. 

 Sepals, petals, and stamens 4 or 5. 



1. Sepals, petals, and stamens 4 (rarely 5 in a few flowers of the 

 same inflorescence). 

 Flowers sessile or subsessile, glomerate, or sometimes solitary. 

 Leaflets 1-3 or wanting, not callus-bearing at the base ; petiole 

 leaf-like, mostly as large as or larger than the leaflets. 



12. Z. Haiti, 



13. Z.jamaicense, 



14. Z '. coriat mm 



15. Z. spinosum. 



