LIFE AND ORGANISATION. 67 



white-bait dinners of a Greenwich season, as affording some 

 practical idea of the numerical demand which the human 

 kitchen makes upon one rare species. And what is this to 

 the amount of life which the whale imbibes and annihilates 

 at a single draught? What estimate of numbers can we 

 put upon the flies of Egypt, or those continuous clouds 

 of locusts, which for days together darken the sky, and de- 

 vastate the fairest regions of the earth ? Instances of this 

 kind might be given without end ; each recording the same 

 marvellous profusion of individual life, made more wonder- 

 ful by the rapid succession of generations as we descend in 

 the scale of being. Take the single instance of the Aphis. 

 By the most certain calculation of the rate of production in 

 this minute creature (weighing scarcely the y oVo ^ a g ram )? 

 it is found that the successive generations from a single 

 Aphis in one warm summer, might amount to a quintillion 

 of living beings ; a number so much above all human com- 

 prehension, that it offers but a vague row of cyphers to the 

 eye. Or take Ehrenberg's estimate of the 140 billions of 

 infusorial animalcules contained in two cubic feet of the Tri- 

 poli slate of Billin, of which rock their siliceous cases form the 

 substance; a wonderful aggregation of individual lives, how- 

 ever we may value the grade of being to which they belong. 

 This marvellous multiplicity, both of individuals and 

 species, is expressed even by the manner in which the de- 

 struction of life takes place on the earth ; and by the vast 

 proportion of the germs and ova of forthcoming life, which 

 never reach maturity. Throughout a great part of the animal 

 creation, there is a strict inter-dependence for that aliment 

 which one species affords to another ; and a constant pressure 

 or struggle, greater or less in degree, to satisfy this necessity. 

 It is the same where vegetable aliment alone is concerned ; 

 the effect in each case being a continual annihilation of life ; 

 - sometimes of species as well as individuals ; and most 



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