BOTANY OF CITRUS FRUITS. 



15 



satile. Pistils two or five, or one and com- 

 pound with two to five or more carpels, in- 

 serted on the more or less elongated recep- 

 tacle. Fruit a capsule, berry, drupe or 

 samara. Seeds oblong or kidney-shaped; 

 embryo straight or curved; endosperm 

 fleshy, sometimes lacking; cotyledons 

 fleshy or foliaceous. Plants mostly native 

 of tropical countries. 



Genus. Citrus Linn., Gen. Plant., Ed. 

 5, 341, 1754. Shrubs or trees, usually with 

 spiny branches. Leaves persistent, unifoli- 

 ate (trifoliate and deciduous in C. trifoliata 

 L.), thick and leathery, dotted with trans- 

 lucent oil glands; petioles generally more 

 or less winged. Flowers axillary, solitary, 

 clustered or in small cymes, white or pur- 

 plish pink, scented; calyx small, cup-like; 

 sepals three to five; petals four to six, or 

 occasionally eight, linear oblong (in C. tri- 

 foliata almost obovate), thick, imbricated; 

 stamens fifteen to sixty, united or sepa- 

 rate, inserted round a cupular or annular 

 disk; ovary 5 8 celled, style soon 

 uous; ovules several in each cell. Fruit a 

 berry, globose, sub-globose or oblong 

 pointed; rind sweet or bitter, well pro- 

 vided with oil cells; juice contained in small fusiform sacks or 

 cells; seeds light colored, testa coriaceous or membranous, em- 

 bryos frequently two or more in each seed; cotyledons fleshy ; 

 hypogeal in germination. Most members of the genus are sup- 

 posed to have had their origin in Cochin China and the Malay 

 Archipelago. Several have become domesticated in Florida and 

 the West Indies. 



Fig. 5. Juice Sacks of 

 Citrus Fruits. A, Trifo- 

 decid- liate orange. B, Sweet 

 orange. C, Sour orange. 

 D, Mandarin orange. E, 

 Pomelo. F, Kumquat. 

 G, Lemon. Two-fifths 

 natural size. 



SPECIES OF CITRUS CULTIVATED IN AMERICA. 



Citrus trifoliata L., Sp. PI. Ed. II, 1101, 1763. A small low 

 branching tree, of strict, upright habit, twelve to fifteen feet in 

 height; young branches angled, older ones rounded, thorny^ 



