135 
Order CII. XANTHOXYLACE^. 
Terebintace^, Juss. Gen. 368. (1789) in part. — Xanthoxyleal, Nees and Martins in 
Nov. Act. Bonn. 11. (1823); Adrien de Jussieu RutacSes, p. 114. (1825). — 
Pteleace.«, Kunth. Ann. des Sc. 2. 345. (1824). — Terebintace^, trib. 6. DC. 
Prodr. 2. 82. (1825). 
Essentiai, Character. — Flowers unisexual, regular. Calyx in 3, or more commonly 
in 4 or 5 divisions. Petals the same number, very rarely none, usually longer than the 
calyx ; cestivation generally twisted, convolute. 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 
female flowers wanting or imperfect. Ovar'y made up of the same number of carpels as 
there are petals, or of a smaller number, either altogether combined, or more or less dis- 
tinct; ovules in each cell 2, collateral, or one above the other, very seldom 4; styles more 
or less combined, according 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 which the sarcocarp is fleshy and partly separable from the endocarp. 
Seeds solitary or twin, pendulous, usually smooth and shining, with a testaceous integu- 
ment ; em6ryo lying within fleshy albumen ; radicle superior ; cotyledons ovate, flat. — Trees 
or shrubs. Leaves without stipules, alternate or opposite, either siinple, or more commonly 
abruptly or unequally pinnate, with pellucid dots. Flowers axillary or terminal, gray, green, 
or pink. The various parts bitter or aromatic. 
Affinities. This is one of the families which comprehend genera with 
both distinct and concrete carpels; the latter are often entirely distinct, even 
in the ovary; but most frequently there is' a union, or at least a cohesion, of 
the styles, by which their tendency to concretion may be recognised. In a few 
instances the cai-pels are absolutely solitary. “ The place originally assigned, 
and for a long time preserved, for most of the genera of Xanthoxylaceae, proves 
sufficiently how near the affinity is between them and (what used to be called) 
Terebintaceae. .If, with Brown and Kunth, the latter are divided into several 
orders, Xanthoxylaceae will be most immediately allied to Burseraceae and Con- 
naraceae, agreeing with the former in the genera with a simple fruit, and With 
the latter in those with a compound one. Notwithstanding the distance which 
usually intervenes in classifications between Aurantiaceae and Terebintaceae, 
there are nevertheless many points of resemblance between them ; Correa de 
Serra has pointed out a passage from one to the other through Cookia ; Kunth, 
in new-modelling the genus Amyris, and in considering it the type of a dis- 
tinct order, suspects its near affinity with Aurantiaceae ; we cannot, therefore, 
be surprised at the existence also of relations between the latter and Xan- 
thoxylaceae. 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 leaves, and which cover the rind of the fruit with opaque 
spaces, — all these characters give the two families a considerable degree of ana- 
logy. This has already been indicated by Jussieu in speaking of Toddalia, and 
in his remarks upon the families of Aurantiaceae and Terebintaceae ;. and it is 
confirmed by the continual mixture, in all large herbaria, of unexamined plants 
of Terebintaceae, Xanthoxylaceae, and Aurantiaceae. The fruit of the latter is, 
however, extremely different ; their seeds resembling, as they do, Terebinta- 
ceae, are on that very account at variance with Xanthoxylaceae, but at the 
same time establish a further point of affinity between them and some Ruta- 
ceous plants which are destitute of albumen. Unisexual flowers, fruit sepa- 
rating into distinct cocci, seeds solitary or twin in these cocci, enclosing a 
usually smooth and blackish integument, which is even sometimes hollowed 
out on its inner edge ; a fleshy albumen surrounding an embryo the radicle of 
which is superior, are all points of analogy between Xanthoxylaceae and Eu- 
phorbiaceae, particularly between those which have in their male flowers from 
4 to 8 stamens inserted round the rudiment of a pistil, and in the female 
flowers cells with 2 suspended, usually collateral, ovules. Finally, several 
