BOTANY. <)9 



Monoecia. The flowers in Euphorbiaceae vary much in the number of tlieir 

 parts. Sometimes the general peduncle or rachis becomes flattened and leaf- 

 like. The inflorescence is occasionally amentaceous, as hi tlie division Scc- 

 paceae, which is separated, as a distinct but not full}- defined order, by Lind- 

 ley. The plants of the order abound in warm regions, especially in Equinoc- 

 tial America, where they occur as trees or bushes, or lactescent herbs, and 

 often present the appearance of Cactuses, from which their milky juice at 

 once distinguishes them. They are also found in North America and in Eu- 

 rope. There are about 192 genera arranged in six sub-orders, and over 2500 

 species. 



Tribe 1. EupJinrhiecc, true Euphorbias. Cells one-seeded. Flowers of 

 the two sexes united in a common involucre, resembling a single flower, naked, 

 a single female with many males. Examples : Euphorbia, &.c. 



Tribe 2. Stiirmgiece. Cells one-seeded. Flowers naked or apetalous in 

 amentaceous spikes : one or many in the axil of an often biglandular bract ; 

 the males tAvo- to ten-androus. Examples : Stillingia, Styloceras, Hura, Hip- 

 pomane, &c. 



Tribe 3. Acalyphecc. Cells one-seeded. Flowers apetalous, calyx valvu- 

 lar in the bud, arranged in clusters along a spike, more rarely in racemes. 

 Examples : Acalypha, Tragia, (fcc. 



Tribe 4. Crotonea,. Cells one-seeded. Flowers apetalous. calyx valvular, 

 or imbricated in the bud, disposed in fascicles, spikes, racemes, or panicles. 

 Examples : Crotonopsis, Siphonia, Croton, (fcc. 



Tribe 5. Phyllnnthece. Cells two-seeded. Flowers most generally 

 apetalous, with the calyx imbricated in the bud, solitary or combined in 

 clusters or axillary fascicles. Stamens two to five, rarely more, inserted 

 on the torus in the centre of the flower, free or united. Examples : Phyl- 

 lanthus, &c. 



Tribe 6. BiLvea'. Cells two-seeded. Flowers usually apetalous, with the 

 calyx imbricated in the bud, arranged in clusters or axillary fascicles, more 

 rarely in racemes or spikes. Stamens four to six, inserted around a central 

 rudimentary pistil. Examples : Buxus, Savia, &-c. 



The plants of the order Euphorbiaceae are acrid and poisonous, this 

 property residing chiefly in their milky juices. That of some species of 

 Euphorbia is collected for medicinal purposes. Valuable oils arc also 

 obtained from this order. Thus castor oil is expressed from the seeds of 

 Ricinus communis, a plant which, herbaceous in temperate climates, is a 

 tree in its native locality, India. The seeds of Croton tiglium furnish 

 Croton oil. The fatty matter obtained from the seeds of Stillingia sebifera, 

 the Chinese Tallow Tree, is used in making candles. Cascarilla is the bark 

 of Croton eleutheria and other species. 'J^he boxwood in such re((uest by 

 wood engravers is obtained from Buxus sempcrvirens. The Cassava, or 

 Manioc flour, is a starchy matter (Tapioca), obtained by grinding uj) the 

 root of Manihot utilissima, and washing this Avell with water. The juice is 

 highly poisonous, although the washed pulp is both harmless and palatable. 

 The juice of Siphonia elastica contains much caoutchouc, and furnishes 



99 



