THE SPURGE FAMILY 



EUPHORBIACE.E J. St. Hilaire 



HIS family includes about 210 genera containing some 4000 species 

 of trees, shrubs and herbs with acrid, often milky juice, natives of all 

 parts of the globe. Thty vary greatly, from the most humble herb 

 of the cooler regions to large thick cactus-hke plants, and the noble 

 trees of the tropics. Some are of great economic importance, especially the South 

 American Hevea hrasiliensis J. Mueller, and other species of Hevea, the milky 

 juice of which yields the valuable Para rubber. Another South American plant 

 of great importance is the Cassava, Manihot Manihot (Linnaeus) Lyons, now cul- 

 tivated in all warm countries for the starch contained in the large roots. The seeds 

 of many of the plants of this family yield fixed oils, most of which are more or 

 less irritant and consequently purgative when taken internally; best known of 

 these are Castor oil, expressed from the ripe seeds of Ricinus communis Linnaeus, 

 cultivated for this purpose in warm countries, also that most powerful oil of a simi- 

 lar nature, Croton oil, from Croton Tiglium Linnaeus, native of the East Indies, and 

 Purging nut oil from the seeds of Jatropha Curcas Linnasus of the West Indies. 

 Cascarilla, an aromatic medicinal bark, is produced by the Bahamian shrub Cro- 

 ton eluteria (Linnaeus) Swartz; the poisonous Gum euphorbia is also produced by 

 members of this family. Among ornamental plants the brilliant foliage of vari- 

 ous species of Acalypha and of CodicBum, the latter under the name of Crotons, 

 is well known. The Cactus-like Euphorbias of the Old World are favorite hedge 

 plants in the tropics on account of their spiny armament and the acrid, irritating 

 milky juice that exudes from their stems when broken. The thorny Euphorbia 

 splendens Linnaeus, known as Christ's thorn, is noted for its brilliant scarlet bracts 

 as well as for its grotesque form. Poinsettia pulcherrima (Willdenow) Graham, is 

 a well-known conservator^^ plant, with very large vivid scarlet bracts. 



The Euphorbiacece have very various leaves; they may be alternate, opposite, 

 verticillate, or in the Cactus-like species are often entirely wanting or reduced to 

 scales; they often have glands at their base; stipules present or wanting. The 

 flowers are monoecious or dioecious, regular. The calyx is of several sepals; the 

 petals equal in number to the sepals, sometimes much reduced, or often entirely 

 wanting, the flowers frequently subtended by an involucre of petal-like bracts; 

 stamens few or many in one or more series, their filaments distinct or united; 

 ovary usually 3-celled; ovules i or 2 in each cell, pendulous; styles as many as 

 the cells of the ovary, simple, divided or many-cleft. The fruit is mostly a 3-lobed 

 capsule frequently separating with great force on ripening into 3 2-valved carpels, 



596 



