112 
ance from Malvales to which it materially approaches in habit, and in the 
monadelphous and even indefinite stamens, in the stellate hairs, &c., and also 
from Rhamnales with which Celastraceae very much agree. We find here the 
same tendency to combine the petals into a tube, in Stackliousiacese and Fou- 
quieracese, as occurs so remarkably among Diosmese in the next group. In 
both these cases, however, the petals readily separate at their base, as the fruit 
increases in size. 
Oeder LXXXVIL EUPHORBIACEiE. 
The Euphorbium Tribe. 
Euphorbi.®, Juss. Gen. 385. (1789). — EuPHORBiACEiE, Ad. de Juss. Monogr. (1824) ; 
Lindl. Synops. 220. (1829). 
Essential Character. — Flowers monoecious or dioecious. Calyxlohed, inferior, with 
various glandular or scaly internal appendages ; (sometimes wanting) . Corolla either con- 
sisting of petals or scales equal in number to the sepals, or absent ; sometimes more nume- 
rous than the sepals, sometimes united at the base. Males : Stamens definite or indefinite, 
distinct or monadelphous ; anthers 2-celled. Females : Ovary superior, sessile, or stalked, 
2- 3- or more celled ; ovules solitary or twin, suspended from the inner angle of the cell ; 
styles equal in number to the cells, sometimes distinct, sometimes combined, sometimes 
none ; stigma compound, or single with several lobes. Fruit generally consisting of 3, 
dehiscent cells, separating with elasticity from their common axis. Seeds solitary or twin, 
suspended, with an aril ; embryo enclosed in fleshy albumen ; cotyledons flat ; radicle 
superior. — Trees, shrubs, or herbaceous plants, often abounding in acrid milk. Leaves oppo- 
site or alternate, simple, rarely compound, usually with stipules. Flowers axillary or ter- 
minal, usually with bracts, sometimes enclosed within an involucre. 
Anomalies. Carpels occasionally 2, or more than 3. Ricinus does not milk, except 
in the middle of the summer. 
Affinities. It is usual to consider Euphorbiacese an apetalous order, be- 
cause of the want of a corolla in the genera with which European Botanists 
are most familiar. And accordingly we find these plants sometimes stationed 
near Urticaceee, with which they have scarcely a point in common, except the 
absence of petals, or close by Myristicaceae, with which they have even less 
kindred. But if instead of considering the imperfectly developed genera of 
Europe as typical of the true structure of the order, we look to those of 
tropical countries we shall find that the apetalous character by no means 
holds good with them. In Aleurites, for example, the petals are as much de- 
veloped as in a Malvaceous plant ; the same thing occurs in Jatropha, Elaeo- 
cocca, and others ; and, in fact, upon looking through the genera described by 
Adrien de Jussieu in his Monograph, it appears that out of 61 genera no fewer 
than 32 have petals. The tendency of the order is, therefore, at least as great 
to form petals as to want them. Now, if the sum of the affinity of Euphorbia- 
cese and other orders be calculated, it wiU be found that it is with Malvaceae 
and Rhamnaceae that they most agree, and especially with the former. Their 
habit, and general appearance, are so much alike that one might easily mis- 
take some Crotons, Aleurites, &c., for Malvaceae ; the starry structure of the 
hairs, the monadelphous stamens, the definite number of ovules in a definite 
number of united carpels, are all further and important points of resemblance. 
The relationship of Euphorbiaceae to Rhamnaceae was long ago perceived by 
Jussieu, and has been since adverted to by Adolphe Brongniart {Monogr. des 
Rham. p. 35.). Brown, too, in omitting Euphorbiaceae from the apetalous 
orders, in his Prodromus, may be conjectured to have entertained a similar 
opinion ; and Auguste de St. Hilaire enquires (Plantes Usuelles, no. 18,) whe- 
ther they are not intermediate between Malvaceae and Menispermaceae. 
