CLASSIFlCATIOlN OF ANGIOSPERMS. 



30^ 



Sweet and Bitter Orange tree contain a volatile oil known as Oil 

 OF Neroli, and composed of limonene, geraniol, linalool, etc. The 

 oil from the rind of the fruit is known as oil of orange peel, and 

 is obtained chiefly from Italy and Sicily. It is composed of 

 limonene, citral, citronellol, etc. The oil from the Bitter Orange 

 peel has a superior flavor and is known as Bigaradia oil. The 

 Bergamot Orange is the fruit of the sub-species Bergamia, culti- 

 vated in Europe, but only rarely in the United States. The oil of 

 the rind of the fruit is known as Bergamot oil and consists 



Fig. 158. Transverse section through the leaf of Barosma serratifolia Willd: e, epi- 

 dennal cells of upper surface, the inner walls of which are mucilaginous. The mucilage (m) 

 frequently includes dendritic excretions of hesperidin, which dissolve in solutions of potas- 

 sium hydroxide, giving a yellow color; p, palisade cells, some of which contain rosette aggre- 

 gates of calcium oxalate; c, chlorenchyma, some of the cells containing rosette aggregates 

 of calcium oxalate, also a large vascular bundle (mestome strand) with a stereomatic peri- 

 cycle forming an arch on the dorsal face; d, epidermis of lower (or dorsal) face of the leaf. 

 After Solereder. 



largely of linalyl acetate. In the group of Mandarin or Kid- 

 glove oranges {Citrus nobilis) the fruit is compressed, spherical, 

 5-6 cm. in diameter and with an orange-yellow, loose and easily 

 removable rind. The shaddock or grape-fruit is derived from 

 the sub-species sinensis var. decumana, a tree indigenous to 

 the Malay Archipelago and extensively cultivated in India, Flor- 

 ida, California and elsewhere. The fruits are quite large, some- 

 times weighing several kilograms, and those which are round are 

 the most valuable commercially, being known as Pomelos or 

 Grape-fruits. The Blood Orange is the fruit of the sub-species 

 sinensis var. sangninea. The Otaheite Orange which is ex- 

 tensively cultivated as a dwarf pot plant and the foliage and 

 flowers of which resemble those of lemon, is probably a variety of 



