51 



N. Ord. RUTACEJE. 

 Tribe Aurantiece. 

 Genus Citrus, Linn. 



51. Citrus Aurantium,* jRisso, in Ann. du Museum, xx, p. 181, 



(1813). 



Orange. Siveet Orange. China Orange. Portugal Orange. 



Syn. C. Aurantium, Linn, (in part). 



Figures. Woodville, 1. 188 ; Hayne, xi, t. 28 ; Nees, t. 425 ; Eisso, Hist. 

 Orang., tt. 339. 



Description. A small tree, rarely reaching 20 feet in height, 

 with an upright trunk much branched above, the branches 

 spreading into a regularly shaped, more or less spherical head; 

 bark smooth, greyish-brown on the older branches, dull whitish- 

 green on the younger ones. Leaves evergreen, alternate, often 

 with short, solitary, sharp spines In the axils ; blade oval or ovate- 

 oblong, acute, 3 or 4 inches long, smooth, shining, dark green, 

 paler below, entire or faintly serrate, articulated on the petiole, 

 which is ^ 1 inch long and more or less broadly winged. 

 Peduncles solitary, axillary, usually 1 -flowered, sometimes 2- to 

 6-flowered, smooth, generally shorter than the petiole. Calyx 

 cup- shaped, with 5 short, broad, acute teeth, thick, pale green, 

 persistent. Petals 5, oblong, 1 1, inch long, thick and fleshy, 

 blunt, brilliant white, with yellowish sunken glands on the back, 

 strongly recurved. Stamens 20 25, hypogynous, filaments 

 unequal, flattened, often united at the base in threes or fours, 

 shorter than the petals ; anthers oblong-linear, versatile, bright 

 yellow. Ovary cylindrical, striated longitudinally, with numerous 

 oil-glands below the epidermis, surrounded at the base by a 

 swollen, prominent, rounded disk, 8- or more celled, with several 

 anatropous ovules in each cell attached in two rows to the axile 



* The mediaeval name for the fruit ; also written arantium, and, like the 

 English word Orange, from the Sanskrit Nagaranga, through the Arab Naranj. 



