ABOMA OF PLANTS. 13 



An fibiindance of moisture is required for the growth of certain 

 plants and also for the development of aroma. This is especially 

 true of plants whose habitat may be aquatic or subaquatic; in this 

 case dryness becomes a direct hindrance to growth and likewise 

 lessens the activity of the metabolic processes taking place within 

 the organism. 



On the other hand, many plants are especial lovers of dryness, 

 particularly such as inhabit the western arid tracts and deserts. 

 These excessively' dry regions are not devoid of plant life; neither 

 are they wanting in plants possessing odors. The sages are excel- 

 lent examples of sturdy growers on dry lands, and many are decidedly 

 aromatic, producing oils of excellent quality. 



In both of the above extreme cases, coupled with the dryness or 

 moisture, an abundance of sunshine is usually conducive to the form- 

 ation of volatile oils in plant organs. 



A typical example may be mentioned in the case of lavender. This 

 highly fragrant oil is derived from the plant Lavandula vera^ which 

 grows for the most part in France and England and is much in- 

 fluenced by such factors as soil, dryness, moisture, altitude, and sun- 

 shine. Oils which possess the highest percentage of the odor bearer, 

 linalyl acetate, are usually produced from plants grown on mountain 

 slopes. 



Lamothe* states that the finest grades of lavender plants of the 

 Drome region are grown at the highest altitudes (2,500 feet) in the 

 mountain districts. Plants grown on the lowlands of these moun- 

 tains have been found to be decidedly inferior. Most light soils are 

 well suited to the growth of lavender, but those of a heavy or soggy 

 nature should be avoided. 



The lavender produced in the Mitcham district of England is gener- 

 ally considered to have the most agreeable fragrance. In England the 



I conditions are decidedly different from those occurring in France, both 

 with respect to soil and altitude. A chalky soil seems to be best 

 adapted to the growth of lavender in the Mitcham district. The 

 plant is, however, also grown profitably in the vicinity of Bourne- 

 mouth, Dorsetshire, where the soil consists of sand and clay, with 

 more or less peaty humus.'' Fungous growths, it is stated, harm 



I lavender where the drainage is not perfect. An abundance of humid- 



lity and sunshine is also considered necessary by the English growers. 

 Although it is generally conceded that the English lavender oil 

 is the most fragrant, this property is attributed by Gildemeister, Hoff- 



^mann, and Kremers^ to the invariably low ester content of the oil, 



« I.amothe, M. L. Bnl. Rome-Rertrand Fils., October, lOOs! p. 33. 

 ^Pliarniiicoutical .Journal, vol. ,S.3, 1001), p. .^)32. 



'' (iiklenieistor, Eduard, lloffiuanii, Friedricb, aud Kremors, Edward. Tlie Vola- 

 [tile Oils, p. GOG. 

 195 



