138 TILLEES OF THE GEOUND CHAP. 



in puddings without ever thinking of the poisonous 

 plant from which it comes. 



Another kind of plant furnishes the yams on 

 which the natives of some warm countries largely 

 depend, and yams again are not wholesome unless 

 they are cooked carefully. 



In general, we may say that underground stems 

 and roots supply man with a large part of the 

 necessary carbohydrate, but they are deficient in 

 proteid. In cold countries, therefore, they are 

 supplemented both by some kind of seeds and, 

 where possible, by meat. The meat gives the 

 flavour necessary to make the roots digestible and 

 pleasant to the taste. In warm countries, where 

 meat is less necessary, some of the strong vegetable 

 flavouring matters are used usually to make up for 

 the want of taste possessed by the vegetables 

 themselves. 



In regard to the fruits cultivated by man, we 

 may notice first the great importance of the plants 

 of the Eose family. This family gives us apples, 

 pears, peaches, apricots, plums, cherries, strawberries, 

 and many other of the fruits of warm or cool 

 countries, all of which are wholesome and pleasant, 

 though they do not supply a large amount of 

 actual nutriment. Then "we have in warm countries 

 the vine, a plant of great importance. In this 

 country we think of wine as only a luxury, but in 



