IN EXTRA-TROPICAL COUNTRIES. 201 



Ocimum 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 gratissimum, Linne. 



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 



