100 



fruit of several kinds of Hickory is eaten in America. The timber of all is 

 valuable ; that of J. regia for its rich deep brown colour when polished, and 

 that of Carya alba for its elasticity and toughness. 

 Examples. Juglans, Carj^a. 



LXXXVIII. EUPHORBIACEiE The Euphorbium Tribe. 



Euphorbia, Juss. Gen. 335. (1739.)— Euphorbiaceje, Ad. de Juss.Monogr.nS2A); Lindl. 



Synops. 220. (1829.) 



Diagnosis. Apetalous dicotyledons, with definite suspended ovules, a 3- 

 celled ovarium, diclinous flowers, and embryo in the midst of oily albumen. 

 Anomalies. Carpella occasionally 2, or more than 3. 



Essential Character. — Flowers monoecious or dioecious. Calyx lobed, inferior, with 

 various glandular or scaly internal appendages ; (sometimes wanting.) Sterile Jlowers : Sta- 

 mens definite or indefinite, distinct or monadelphous; anthers 2-celled. Fertile jlowers : 

 Ovarium superior, sessile, or stalked, 2- 3- or more celled ; ovules solitary or twin, suspended 

 from the inner angle of the cell ; styles equal in number to the cells, sometimes distinct, some- 

 times combined, sometimes none ; stigma compound, or single with several lobes. Fruit 

 consisting of 2, 3, or more dehiscent cells, separating with elasticity from their common axis. 

 Seeds solitary or twin, suspended, with an arillus; embryo enclosed in fleshy albumen; coty- 

 ledons flat; radicle superior. — Trees, shrubs, or herbaceous plants, often abounding in acrid 

 milk. Leaves opposite or alternate, simple, rarely compound, usually with stipula;. Flowers 

 axillary or terminal, usually with bracteaj, sometimes enclosed within an involucrum. 



Affinities. If the group of apetalous orders be considered a natural one, 

 Euphorbiaceas will stand by the side, or in the vicinity, of Urticese, with 

 which, however, they have few points in common, except the want of a 

 corolla ; or near Myristiceae, with which the columnar stamens of many 

 species, and the acridity of their juice, may be said to accord. But it is pro- 

 bable that the real relationship of the order is of a very different kind. 

 Jussieu long ago perceived a resemblance between Euphorbiacere and Rham- 

 neae, a resemblance which A. Brongniart has since adverted to, (J\tonogr. des 

 Rhamn. p. 35,) and which chiefly depends upon a similarity in habit, an em- 

 bryo with flat foliaceous cotyledons, solitary seeds, a great reduction in size of 

 the petals of Rhamnere, as if the order was tending towards an apetalous 

 state, and a frequent division of the fruit into three parts. Auguste St. Hilaire 

 (PL Usuelles, no. 18.) inquires whether they are not intermediate between 

 Menispermea; and Malvaceae. There can be no doubt of their relation to the 

 latter, that is to say, to the orders of polypetalous dicotyledons with lvypogy- 

 nous stamens and a valvate calyx, if we consider their general habit, espe- 

 cially that of the Crotons, the presence of abundance of stellate hairs, and 

 their definite seeds ; but these points are not sufficient to approximate the 

 orders very nearly : in fact, the true affinities of Euphorbiacea) cannot be said 

 to be at present well understood. Ach. Richard suggests some affinity with 

 Terebintacere, as well as Rhamneas. Eldmens, ed. 4. 558. 



Geography. This extensive order, which probably does not contain fewer 

 than 1500 species, either described or undescribed, exists in the greatest 

 abundance in equinoctial America, where about 3-8ths of the whole number 

 have been found ; sometimes in the form of large trees, frequently of bushes, 

 still more usually of diminutive weeds, and occasionally of deformed, leafless, 

 succulent plants, resembling the Cacti in their port, but differing from them 

 in every other particular. In the Western world they gradually diminish as 

 they recede from the equator, so that not above 50 species are known in North 



