THALAMIFLOR^. 235 



tree ; its bark, and that of Cedrela Toona, febrifuya, and other species, 

 are used as substitutes for Cinchona. Chloroxylon Swietenia furnishes 

 East-Indian Satin-wood j and an oil called Wood-oil is obtained from it. 

 Oxleya xanthoxyla is the Yellow- wood of Australia. 



AUBANTIACE^. THE ORANGE ORDER. 

 Series Discifloras ; Tribe of Kutaceae, Benth. et Hook. 



Diagnosis. Trees or shrubs with smooth, glandular alternate leaves, 

 the blade jointed to the petiole; flowers regular, hermaphrodite, 3-5- 

 merous ; petals and stamens inserted on an hypogynous disk ; stamens 

 with flat filaments, distinct or coherent into one or several parcels ; ovary 

 many-celled, style single, terminal ; fruit pulpy, often with a glandular 

 leathery rind ; seeds without perisperm ; embryo with thick fleshy cotyle- 

 dons and a short radicle next the hilum. Illustrative Genera : Triphasia, 

 Lour. ; Beryera, Keen, j Cookia, Sonner. ; Feronia, Corr. j JEgle, Corr. ; 

 Citrus, L. 



Affinities, &c. The plants of this Order are by Bentham and Hooker 

 classed as a tribe of Rutaccce, and are nearly related to the Meliaceae in the 

 structure of the flowers, and still more closely to Amyridacese. In general 

 they are distinguishable by the dotted leaves, with the blade (simple or 

 compound) articulated to the petiole, the deciduous imbricated petals, 

 and the succulent fruit. The relation to Eutaceae is rendered clearer by 

 occasional monstrosities of the fruit, from which some of the carpels grow 

 out like horns. Sometimes a second circle of carpels is produced, forming, 

 as it were, a double concentric fruit, comparable in some measure to the 

 conditions in the Pomegranate, where, however, the whole fruit is en- 

 closed in the excavated receptacle. The pulp of the Orange consists of 

 cellular hairs produced from the wall of the fruit. The seeds of Oranges 

 often contain two embryos; and they are remarkable for the develop- 

 ment of ramified collections of spiral vessels at the chalazal end, within 

 the testa, also for a peculiar coloration of the inner coat of the seed in 

 this situation. 



Distribution. Chiefly East-Indian plants, but diffused by cultivation 

 throughout the tropics, and even in the warmer temperate regions. 



Qualities and Uses. The most remarkable parts of these plants are 

 their fruits ; those of the genus Citrus being among the most valuable and 

 best-known of imported fruits. The species of Citrus are not clearly de- 

 fined, much difference of opinion existing as to the specific distinctness of 

 certain forms, which, as in most cultivated plants, are much confused. 

 C. Aurantium is the common Sweet Orange ; C. Biyaradia or C. vulgwify 

 the bitter or Seville Orange, seems to be known only in cultivation, and 

 is supposed by some to be a variety of the preceding. C. Beryamia is the 

 Mellarosa or Bergamot Orange, which is also regarded as a variety ol C. 

 Limetta, the cultivated Sweet Lime ; C. acida is the East-Indian Lime ; , 

 C. Limonwn is the ordinary Lemon ; C. Lwnia is the Sweet Lemon, cul- 

 tivated in the South of Europe; C. medica is the Citron; C. decumana is 

 the Shaddock ; C. Paradisi the Forbidden-fruit ; C. Pompeimos the Pom- 

 pelmoose ; and C. japonica the Kumquat. All these fruits have an 

 abundant pulp, which varies chiefly in the degree of acidity and the 



