84 THE GEOGRAPHY OF PLANTS. 



ing plants, while in tropical Australia and 

 India the proportion is as one to twenty-six. 

 The cocoa-nut abounds ; the bread fruit, of 

 which fifty varieties are indigenous, yields 

 three or four crops annually. The banana, 

 (Musa paradisaica^ with several allied species 

 and varieties, is plentiful throughout the 

 islands ; an acre of ground, planted with ba- 

 nanas, will produce one hundred and thirty- 

 three times as much food as if planted with 

 wheat, and forty-four times as much as with 

 potatoes. Still, as the -banana is not so nutri- 

 tious as these, it will not suffice to support so 

 many individuals as would appear at first from 

 these statements. Humboldt calculates that a 

 banana plantation will support about twenty- 

 five times as many individuals as the same 

 extent of ground sown with wheat. Perhaps 

 there is no other plant whose produce is so im- 

 mense. It is to the inhabitants of some tropical 

 countries what wheat, barley, and rye, are to 

 the inhabitants of Europe and Western Asia, 

 and what the numerous varieties of rice are to 

 those of the countries beyond the Indus. The 

 labour of cultivating it is very slight, and its 

 growth very rapid, while it flowers and bears fruit, 

 through the whole year. Humboldt remarks, 

 that a European traveller, newly arrived in the 

 torrid zone, is struck with nothing so much as 

 the extreme smallness of the spots under culti- 

 vation round a cabin which contains a numer- 

 ous family of Indians. Thirty-six good-sized 

 fruits are sufficient to support a man entirely for 



