274 



EUPHORBIACE^. 



[Diclinous Exogens. 



Order XC. EUPHORBIACEtE.— Spurgeworts. 



Euphorbiae, Juss. Gen. 385. (1789). — Euphorbiace3e,^(f. deJuss. Monogr. (1824) ; Endl. ccxliii. ; Meis- 

 Tier, p. 336 ; Klotzsch in Erichs. Archiv. 7. 175. (1841).— Trewiacese, Ed. prior, p. 174. — Pseudan- 

 theae, Endl. p. 328.— Anthoboleae, Endl. p. 328 ?— Putranjivese, Endl. p. 287. 



Diagnosis. — EupJiorhial Exogens, loith definite susjjended anatropal ovxdes, scattered 

 floivers, and tricoccous fruit. 



Trees, shmbs, or herbaceous plants, often abounding in acrid milk. Leaves opposite 

 or alternate, simple, rarely compoimd, often \A'ith stipules. Flowers axillary or terminal, 



CLXXXVII, 



arranged in various ways, sometimes inclosed within an involucre resembling a calyx. 

 Flowers ^ $ . Calyx inferior, ^vith various glandular or scaly internal appendages ; 

 (sometimes wanting.) Corolla either consisting of petals or scales equal in number to 

 the sepals, or absent, or sometimes more numerous than the sepals ; sometimes monope- 

 talous. (J Stamens definite or indefinite, distinct or monadelphous ; anthers 2-celled, 

 sometimes opening by pores. $ Ovary free, sessile, or stalked, 1-2- 3- or more celled ; 

 ovules solitary or twin, suspended from the inner angle of the cell ; styles equal in num- 

 ber to the cells, sometimes distinct, sometimes combined, sometimes none ; stigma com- 

 pound, or single with several lobes. Fruit generally tricoccous, consisting of 3 carpels 

 splitting and separating with elasticity from their common axis, occasionally fleshy and 

 indehiscent. Seeds solitary or twin, suspended, often with an aril ; embryo inclosed in 

 fleshy albumen ; cotyledons flat ; radicle superior. 



No group of plants can illustrate better than this the entangled nature of botanical 

 affinities ; for it claims kindred in an almost equal degree with Nettleworts, because of its 

 unisexuality, and with Rhamnads and Mallow^vorts when that ch'cumstance is left out of 

 consideration. By the school of Jussieu it is considered an apetalous Order, with a 

 tendency to form a corolla ; by myself and others it is regarded as a polypetalous Order, 

 losing its petals in a part of the species. 



The reason for considering Spm'geworts as an apetalous Order is because of the want 

 of a corolla in the genera with which Em'opean Botanists are most familiar. But if, 

 instead of considering the imperfectly developed genera of Em'ope as typical of the true 

 structm'e of the Order, we look to those of tropical countries, we find that the apetalous 

 character by no means holds good with them. In Alemites, for example, the petals are 

 as much developed as in a Malvaceous plant ; the same thing occm's in Jatropha, Elseo- 

 cocca, and others ; and, in fact, upon looking tlu'ough the genera described by Adrien de 

 Jussieu in his Monogi*aph, 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 fonn petals as to want them. 

 Now^ if this be so, and the separation of sexes be disregarded, it will be found 

 that it is with Mallowworts, on the one hand, and Rhamnads, on the other, that they 



Fig. CLXXXVII.— Andrachne telephioides. 1. A male flower ; 2. a female flower ; 3. a pistil VNith 

 the scales at its base ; 4. a transverse section of an ovary ; 5. a ripe seed ; 6. a vertical section of it. 



