258 E UPHORBIA CEAE 



Most are shrubs or trees, a few herbaceous (e.g. the Brit. sp.). 

 Many are xero. ; a number of Australian sp. are of ericoid habit ; 

 several, esp. S. Afr., Euphorbias are cactus-like; others resemble 

 Lauraceae, or possess phylloclades (e.g. Phyllanthus sp.). A few are 

 lianes. L. usu. alt.; some have opp. 1., some opp. 1. above and alt. 

 below. Slips, usu. present, but may be repres. by branched hair- 

 like bodies (Jatropha), glands, or thorns. Nearly all contain latex in 

 special laticiferous cells. 



Infl. usu. complex ; almost every type occurs. Often the first 

 branching is racemose and all subsequent ones cymose. In some 

 cases, e.g. Dalechampia and Euphorbia (q-v-), the partial infls. are 

 so condensed as to give the appearance of single fls. The fls. are 

 always unisexual, monoec. or dioec. , reg., hypog. The P may be 

 present as two whorls usu. j-merous; more often there is only one 

 (calyx) and .frequently the fl. is naked. Sta. i oo , free or united 

 in various ways. Ricinus has branched sta. Phyllanthus cydanthera 

 has the sta. united, with a ring-like common anther. G usu. (3), 

 with axile placentae, and 3 loc. Styles usu. 2-lobed. The ovules 

 are constant throughout the family and form its best distinctive 

 feature; they are i or 2 in each loc., collateral, pendulous, ana- 

 tropous, with ventral raphe. The micropyle is usu. covered by a 

 caruncle, which is also found on the seed. The fruit is almost 

 invariably a ' schizocarp-capsule. ' It splits into cpls. often elastically, 

 and at the same time each cpl. opens ventrally, letting the seed 

 escape. See albuminous. [BH. chars, incl. those of Buxaceae, esp. 

 dorsal raphe, and loculic. caps, or drupe.] 



Most E. are poisonous. Several are important economic plants, 

 e.g. Manihot (rubber, cassava), Hevea (rubber), Croton, Ricinus, &c. 



Classification and chief genera (after Pax) : 



A. PLATYLOBEAE (cotyledons much broader than radicle) : 



I. PHYLLANTHOIDEAE (ovules 2 per loc. ; no latex) : 



i. Phyllantheae (embryo large, little shorter than endosp. ; $ 

 calyx imbricate) : Phyllanthus. 



i. Briddieae (do., but 3 calyx valvate): Bridelia. 



3. Daphniphylleae (embryo short, 4 6 times shorter than en- 

 dosp.) : Daphniphyllum. 



II. CKOTONOIDEAE (ovules i per loc. ; latex usu. present): 



1. Crotoneae (sta. bent inwards in bud) : Croton. 



2. Acalypheae (sta. erect in bud; fl. usu. apetalous; c? calyx 



valvate; infl. a raceme, spike, or panicle, axillary or term.): 

 Mercurialis, Acalypha, Ricinus, Dalechampia, Tragia. 



3. Jatropheae (do. ; infl. a dichasial panicle): Hevea, Jatropha. 



4. Adnaneae (do.; infl. a simple term, spike or raceme): 



Manihot. 



5. Cluytieae (s calyx imbr. ; i fls. with petals, in groups or 



cymes, these partial infls. axillary or in complex infls.): 

 Codiaeum, Cluytia. 



6. Gtlonieae (do. but apetalous) : Gelonium. 



7. Hippomaneae (do.; apetalous; infl. axillary or term., spike- 



like, the partial infl. cymes) : Stillingia, Hura, Hippo- 

 mane. 



