THALAMIFLOE^. 



493 



C. guianensis also yield a somewhat similar oil, which possesses analogous 

 properties. The bark of these species possesses febrifugal properties. 



Natural Order 50. Aurantiace^. ■ 

 897— 899).— General Character.- 



- The Orange Order (Jigs. 

 ■Trees or shr^bs. Leaves 



Fig. 897. 



Fig. 898. 



Fig. 899. 



Fig. 897. Diagram of the flower of the Orange (Citrus Auraniium) Fig.S98. 



Vertical section of the ovary, showing a portion of the disk at its base, and a 



solitary hypogynous stamen Fig. 899. Pistil of the Orange, with disk at its 



base, and the calyx : the petals and other stamens have been removed. 



alternate, commonly smooth, exstipulate, dotted, and with the 

 blade articulated to the petiole (Jig. 300), which latter is 

 usually winged. Flowers regular, fragrant. Calyx short (Jig. 

 899), urn-shaped or campanulate, 3 — 5-toothed (Jigs. 897 

 and 899), withering. Petals equal in number to the divisions 

 of the calyx (Jig. 897), distinct or slightly coherent at the base, 

 imbricated, inserted on a hypogynous disk. Stamens equal in 

 number to the petals, or some multiple of them (Jig. 897) ; Jita- 

 ments flattened at the base, either distinct, or coherent into one 

 or several bundles (Jig. 541) ; inserted along with the petals on 

 the disk. Disk hypogynous, annular (Jigs. 898 and 899). Ovary 

 many-celled (Jig. 897); style 1 (Jigs. 898 and 899); stigvia 

 enlarged (Jig. 899), and slightly divided ; ovules solitary or 

 numerous. Fruit indehiscent (Jig. 695), constituting what has 

 been termed a hesperidium, 1 or many-celled ; occasionally its 

 component carpels become more or less separated, and form what 

 have been termed fingered Citrons and horned Oranges ; or the 

 number of carpels becomes increased (fg. 696), so that one fruit is 

 produced within another. Seeds soUtary or numerous ; placentas 

 axile (Jigs. 695 and 898), sometimes containing more than one 

 embryo; the raphe and chalaza generally very evident, ex- 

 albuminous ; embryo straight, with thick fleshy cotyledons, and 

 a short radicle next the hilum. 



Diagnosis. — Trees or shrubs with alternate, dotted, exstipulate 

 leaves, having the blade articulated to the petiole. Flowers 



