472 



XANTHOXYLACE^. 



[HyPOGYNOUS ExOGEiVS. 



Order CLXXVII. XANTHOXYLACE^.— Xanthoxyls. 



Terebintacese, Juss. Gen. 368. (1789) i}i part.— 'Kanthoxyleie, Neesand Martius in Nov. Act. Bonn. 11. 

 (1823) ; Adrien Ce Jussieu Rutacees, p. 114. (1825) ; Endl. Gen. ccl. ; Wifjht. Illust. 1. 168.— Pte- 

 leaceae, Kunth. Ann. desSc. 2. 345. (1824).-TerebintaceaB, trib. 6. DC. Prodr. 2. 82. (1825). 



Diagnosis. — Rutal Exogens, tvith a few-seeded fi^it which finally becomes apocarpous and 

 separates its pericarp into distinct layers, sessile pendulous ovules, and ^-0- $ 

 flowers. 



Trees or shrubs. Leaves without stipules, alternate or opposite, either simple, or 

 more commonly abruptly or unequally pinnate, with pellucid dots. Flowers axillary or 

 tenninal, gray, green, or pink, 

 ? - ^ - J , regular. Sepals im- 

 bricated, 3, or more com- 

 monly 4 or 5. Petals the 

 same number, very rarely 

 none, usually longer than the 

 calyx ; aestivation generally 

 imbricated. Stamens equal 

 to the petals in number, or 

 twice as many, arising from 

 around the base of the stalk 

 of the abortive carpels ; in 

 the $ wanting or imperfect. 



Ovary made up of the same number of carpels as 

 there are petals, or of a smaller number, either alto- 

 gether combined, or more or less distinct ; o%'ules 

 in each cell 2, collateral, or one above the other, 

 very seldom 4 ; styles more or less combined, ac- 

 cording to the degree of cohesion of the carpels. 

 Fruit either berried or membranous, sometimes of 

 from 2 to 5 cells, sometimes consisting of several 

 drupes or 2-valved capsules, of wliich the sarcocarp 

 is fleshy and partly separable from the endocarp. 

 Seeds solitary or twin, pendulous, usually smooth 

 and shining, vath. a testaceous integument ; embryo 

 lying within fleshy albumen ; radicle superior ; 

 cotyledons ovate, flat. 



If we neglect the constant tendency which the 

 Order of Xanthoxyls has to produce unisexual 

 flowers, we shall have no good character to distin- 

 guish it from Rueworts. If the dry apocarpous, 

 dehiscent character of the fruit is left out of consi- 

 deration it vAW merge in Citronworts, among 

 which Lu^'unga climbs Uke a Xanthoxylum. Cor- 

 rea de SeiTa has also pointed out a passage from 

 one to the other through Cookia. " A mixture of 

 bitter and aromatic principles, the presence of re- 

 ceptacles of oil that are scattered over every part, 



which give a pellucid dotted appearance to the pig. CCCXXVII. 



leaves, and which cover the rind of the fruit with 



opaque spaces,— all these characters give the tAvo families a considerable degi'ee of ana- 

 logy. This has ah'eady been indicated by Jussieu in speaking of Toddalia, and in liis 

 remarks upon the families of Citronworts and Anacards ; and it is confii-med by the 

 contmual mixtm-e, in all large herbaria, of miexamined plants of Anacards, Xantho- 

 xyls, and Citronworts. The fmit of the latter is, however, extremely different ; their 

 seeds resembhng, as they do, Anacards, are on that very account at vainance with 

 Xanthoxyls, but at the same time estabhsh a fm-ther point of affinity between them 

 and some Rutaceous plants which are destitute of albumen. Unisexual flowers, fruit 

 separating into distinct cocci, seeds soUtary or twin in those cocci, inclosing a usually 



Fig. CCCXXVII.— Toddalia florlbunda. 1. a flower; 2. 

 ovule ; 3. fniits ; 4. a perpendicular section of one of them. 



a pail- of carpels, one of which shows it." 



