OLEACE^E 833 



CONSPECTUS OF THE ARBORESCENT GENERA OF THE UNITED STATES. 



Fruit a winged samara; leaves usually compound. 1. Fraxinus. 



Fruit a drupe; leaves simple. 



Flowers usually without petals. 2. Forestiera. 



Flowers with petals. 



Corolla of 4 long linear petals united only at base; leaves deciduous. 



3. Chionanthus. 

 Corolla tubular; leaves persistent. 4. Osmanthus. 



1. FRAXINUS L. Ash. 



Trees or shrubs, with thick furrowed or rarely thin and scaly bark, usually ash-colored 

 branchlets, with thick pith, and compressed obtuse terminal buds much larger than the 

 lateral buds. Leaves petiolate, unequally pinnate or rarely reduced to a single leaflet, de- 

 ciduous; leaflets conduplicate in the bud, usually serrate, petiolulate or sessile. Flowers 

 dioecious or polygamous, produced in early spring on slender elongated pedicels, without 

 bractlets, in open or compact slender-branched panicles, with obovate linear or lanceolate 

 caducous bracts, terminal on leafy shoots of the year, developed from the axils of new leaves, 

 or from separate buds in the axils of leaves of the previous year, or at the base of young 

 branchlets, and covered by 2 ovate scales; calyx campanulate, deciduous or persistent under 

 the fruit, or 0; corolla 2-4-parted, the divisions conduplicate in the bud, united at base, or 

 0; stamens usually 2, rarely 3 or 4, inserted on the base of the corolla, or hypogynous; fila- 

 ments terete, short or rarely elongated; anthers ovoid or linear-oblong, the cells opening by 

 lateral slits; ovary 2 or rarely 3-celled, contracted into a short or elongated style terminat- 

 ing in a 2-lobed stigma; ovules suspended in pairs from the inner angle of the cell; raphe 

 dorsal. Fruit a 1 or rarely 2 or 3-seeded winged samara; body terete or slightly flattened 

 contrary to the septum, with a dry or woody pericarp produced into an elongated more or 

 less decurrent wing, usually 1-celled by abortion or sometimes 2 or 3-celled and winged. 

 Seed solitary in each cell, oblong, compressed, gradually narrowed and rounded at the ends, 

 filling the cavity of the fruit; seed-coat chestnut-brown. 



Fraxinus with thirty to forty species is widely distributed in the temperate regions of the 

 northern hemisphere, and within the tropics occurs on the islands of Cuba and Java. Of 

 the eighteen North American species here recognized all, with the exception of Fraxinus 

 dipetala Hook., of California, are large or small trees. 



Fraxinus produces tough straight-grained valuable wood, and some of the species are 

 large and important timber- trees. The waxy exudations from the trunk and leaves of 

 Fraxinus Ornus L., of southern Europe and Asia Minor furnish the manna of commerce 

 used in medicine as a gentle laxative; and the Chinese white wax is obtained from the 

 branches of Fraxinus chinensis Roxb. 



Fraxinus is the classical name of the Ash-tree. 



CONSPECTUS OF THE* NORTH AMERICAN ARBORESCENT SPECIES. 



Flowers with a corolla, in terminal panicles on lateral leafy branchlets of the year; leaflets 

 3-7, lanceolate to ovate-lanceolate (ORNUS). 1. F. cuspidate (E, H). 



Flowers without a corolla, dioecious or polygamous, in axillary panicles, from separate buds, 

 in the axils of leaves of the previous year (FRAXINASTRUM) . 

 Flowers with a calyx. 



Leaflets with obscure veins, not more than f ' long; fruit narrow-spatulate to oblong- 

 obovate; rachis slightly winged. 2. F. Greggii (E). 



Leaflets with distinct veins, more than f ' long; rachis without a wing. 

 Body of the fruit compressed, its wing extending to the base. 

 Branchlets 4-sided. 



Leaves usually 5-foliolate, with ovate acute leaflets; flowers unknown. 



3. F. Lowellii (F). 



