IMPORTANCE OF THE TRIBE TO MAN. 563 



important benefit in certain situations ; such are the Date and 

 the Cocoa Nut. But these are valuable, just because the 

 Grasses, which are otherwise universal in their distribution, are 

 prevented, by peculiarities of climate or other causes, from flou- 

 rishing in those particular spots. In all but the very coldest 

 parts of Europe, we find some of the corn-grains affording the 

 principal supplies of food ; barley and oats in the north, rye in 

 latitudes a little more southern, and then wheat. In the 

 Southern parts of Europe, rice and maize come into ordinary 

 cultivation ; and the use of these extends throughout the tropics. 



738. The various provisions for the natural propagation of 

 these important vegetables are extremely interesting. The 

 animals which browse upon them usually prefer the foliage, 

 leaving the flower-stalks to ripen their seed ; or, if they destroy 

 both, the plant spreads by offsets from the underground stems. 

 Even if they be trodden down, they are not destroyed ; for 

 buds are developed from the several nodes of the stem, which 

 thus multiply the plant. It is on exposed downs and barren 

 places, where the heat is insufficient to ripen the seeds, and 

 where there is no germination, that we find the tendency to 

 multiply by buds most remarkable. 



739. It may give some idea of the enormous amount of sub- 

 sistence afforded by the Grasses, to state that, some years ago, 

 when the population of Britain was much less than it is at pre- 

 sent, it was calculated, after a laborious series of investigations, 

 that 416 million bushels of corn are annually consumed in Bri- 

 tain, besides 100,000 bags of rice, and 200,000 tons of sugar. 

 It has been estimated that there are upwards of a million of 

 horses employed in Britain in different ways, each requiring as 

 much vegetable food as would support eight men ; the value of 

 their pasturage, therefore, must be fully one-third of that from 

 which the quantity of corn just mentioned is produced. Fur- 

 ther, it has been stated that, not computing pork, bacon, or 

 poultry, upwards of 150 million pounds of meat are annually 

 consumed in London alone ; and this amount should probably be 

 multiplied by at least ten, to represent the consumption of the 

 country in general. Again, it has been calculated that the value 



