696 CCH. EUPHOEBIACE^J. 



* * Flowers in the axils of bracts, not involucrate; brack at first connate, then splitting and 



resembling an involucre. 

 Sub-tribe XV. HUREJ:. Flower not compressed. Stamens central. Hura, &c. 



* * * Flower enclosed in a calyciform involucre. 

 Sub-tribe XVI. PHYLLOBOTRYEJ;. Stamens central, disk 0. Phyllobotryum. 



TEIBE IX. DALECHAMPIE^J. 



Ovarian cells 1-ovuled. Anthers erect in bud. Flowers involucrate. Involu- 

 cres 2-sexual, i.e. bearing $ and ? flowers. Calyx of $ valvate in aestivation. 

 Involucre compressed, 2-phyllous. Flowers <? polyandrous. 



GENUS. 

 Dalechampia. 



TRIBE X. EUPHORBIE^J. 



Ovarian cells 1-ovuled. Anthers erect in bud. Flowers involucrate ; involucres 

 2-sexual. Calyx of $ (rarely developed) quincuncial in aestivation. Involucre 

 calyciforin, not compressed. Flowers $ monandrous. 



PRINCIPAL GENERA. 

 Authostema. Synadenium. * Euphorbia. Calycopeplus. Pedilanthus. 



[The genus Daphniphyllum, separated from Euphorbiacece by J. Miiller, and 

 erected into a natural order, differs from the latter only in the small embryo, and 

 the ovule with a ventral raphe. They are Indian shrubs of mountainous districts, 

 extending from the Himalayas to Java, China, and Japan, and there is also a West 

 Indian species. ED.] 



The great family of Euphorbiacece presents numerous affinities. Thus they approach Malvacece in 

 habit, pubescence, stipulate leaves, often monadelphous stamens and loculicidal fruit; they differ in the 

 nature of their secretions, in diclinism, the position of the ovules, and the structure of the seed. They 

 are connected with Urticece, but the latter are separated by their 1-celled ovary, simple style, solitary 

 orthotropous ovule, 1-celled indehiscent fruit, persistent calyx, &c. They approach Rhamnece in habit 

 (Bridelia), but these are easily distinguished by the hermaphrodite flowers, the position and direction of 

 the ovules, and the situation of the stamens relatively to the petals. Menispermete also resemble in their 

 flower some Euphorbiacece, but are distinguished by the arrangement of their free carpels. 



About half the species inhabit equatorial America; they are much rarer in temperate America. In 

 the Old World they are more abundant in the Mediterranean region and in temperate Asia than between 

 the tropics. The vast genus Euphorbia, comprising more than 700 species, is dispersed over the whole 

 world, except in alpine and cold localities. 



The properties of Euphorbiacece are as distinctive as their botanical characters, and the ancients had 

 so accurately recognized this, that all plants with a 3-coccous fruit were regarded by them as hurtful and 

 suspicious. Euphorbiacece secrete a very acrid milky juice, varying in strength with the species, the cli- 

 mate, and the organ of the plant. In some this juice is one of the most deleterious of poisons, in others 

 its acridity is so far neutralized by mucilage and resins as to reduce it to a simple purgative and diuretic. 

 Some species are slightly narcotic-acrid, others aromatic. The albumen usually contains a fixed oil, 

 without the acridity which is found in the embryo and integuments of the seed. It is to a liquid resin 

 and a volatile principle that all the properties of Euphorbiacece are due ; they are thus strongest in 

 alcoholic tir.ctures, but are dissipated or weakened by the application of heat. The root of the 

 Manihot offers a remarkable example : there is scarcely a more poisonous juice than this, yet the action 

 of fire converts the plant into very wholesome food. 



Euphorbia, the typical genus, is very various in habit : some species have a fleshy angular stem, 



