J4 CITRUS FRUITS AND THEIR CULTURE. 



^^^^ quently been noted in the same 



* species. Fig. 4 D. shows the usual 



shape of the oil cells in the rind 



ofLnQn\/ktoOQiifiQ- of the mandarin oranges. The il- 

 lustration represents those of the 

 China mandarin. Yet in the rind 

 of Beauty, a variety of mandarin 

 closely related to China and truly 

 a member of the group, the oil cells 

 are distinctly oval or double con- 

 vex. They are scattered through 

 the white fungous portion of the 

 rind and may be readily dissected 

 out. 



It is believed that the juice 

 sacks of the pulp, their size, shape 

 and appearance in the cut surface 



rig. 4 . oil ceiis in the Rind of tlle f t can be used to some 

 of citrus Fruits. A, Trifo- extent as a diagnostic feature in 



liate orange. B, Sweet or- 

 ange, c, sour orange. D, classification, a point which seems 



Mandarin orange. E, Po- 



melo- F ^ Kutnquat - K G - to have been quite general Iv over- 

 Lemon. The distance be- 

 tween the line on which the looked. The juice sacks of a num- 



cells rest, and the next line 



above represent the thick- fo er o f fl^ gpeciCS are ShOWU in 



ness of the rind. Enlarged 



IV, times. Fig. 5. 



Family. Rutaceae, Juss. Gen., 296, 1789. Trees or shrubs, 

 rarely herbs, with aromatic alternate or opposite, usually com- 

 pound leaves, dotted with translucent glands containing an 

 essential oil. Flowers generally in axillary or terminal cymes, 

 though sometimes occurring singly. Sepals four to five or 

 lacking. Petals four to five, hypogynous or perigynous. Sta- 

 mens as many or twice as many as the petals (in Citrus and 

 ^Egle more), separate or united, inserted on the receptacle; 

 anthers two-celled, opening along the inner face, generally ver- 



