IN EXTRA-TROPICAI, COTINTRIES. 201 



Ocimnm Basilicum, Linne. 



The Basil. Warmer parts of Asia and Africa. An annual 

 herb, valuable for condiments and perfumery. Several varie- 

 ties exist, differing considerably in their scent. A crystalline 

 substance is also obtained from this and similar species. O. 

 canum (Sims) is closely allied. 



Ocimum gratissimnm, Linn^. 



Recorded from India, the South Sea Islands, and Brazil, as 

 indigenous. Somewhat shrubby. This is also a scent plant 

 like the following, and is one of the best of the genus. O. 

 viride (Willd.) from tropical Africa seems a variety. 



Ocimum sanctum, Linne. 



Arabia, India, tropical Australia. A perennial herb. The 

 odour of the variety occurring in North Australia reminds of 

 anise ; the smell of the variety growing in East Australia 

 resembles cloves. O. tenuiflorum, L., seems to be another 

 variety. Probably other species, cis- as well as trans-Atlantic, 

 can be used like Basil. 



Ocimum suave, Wildenow. 



East Africa. A scrubby species. 



Olea Europsea, Linne.* 



The Olive Tree. From South- Western Asia ; naturalised in 

 the countries around the Mediterranean Sea. A tree not of 

 great height, but of many centuries' duration and of un- 

 abating fecundity. The well-known olive oil is obtained 

 from the fruit. Certain varieties of the fruit, preserved in 

 vinegar or salt-liquid before perfectly ripe, are also much 

 used for the table. For this purpose the fruit is generally 

 macerated previously in water containing potash and lime. 

 The gum-resin of the Olive Tree contains the crystalline 

 olivil. The oil of the drupaceous fruit is a most important 

 product of countries with a temperate climate. Its chemical 

 constituents are: 30 per cent, crystalline palmitin; 70 per 

 cent, olein, through which olive oil belongs to those kinds 

 which are not drying. In pressing, the kernels must not be 

 crushed, as then a disagreeable taste will be imparted to the 

 oil. The wild variety of the olive tree has usually short 

 blunt leaves and thorny branches. Long-continued droughts, 

 so detrimental to most plants, will affect the olive but slight- 

 ly, It thrives best on a, free, loamy, calcareous soil, even should 

 it be strong and sandy, but it dislikes stiff clay. Proximity 



