GROWTH. 143 



this excess of force in locomotion. But as implied above, and 

 as will presently be shown, another factor of importance comes 

 into play; so that perhaps the safest evidence that there is 

 an antagonism between the increase of bulk and the quan- 

 tity of motion evolved is that supplied by the general experi- 

 ence, that human beings and domestic animals, when over- 

 worked while growing, are prevented from attaining the ordi- 

 nary dimensions. 



One other general truth concerning degrees of growth, 

 must be set down. It is a rule, having exceptions of no 

 great importance, that large organisms commence their 

 separate existences as masses of organic matter more or less 

 considerable in size, and commonly with organizations more 

 or less advanced; and that throughout each organic sub- 

 kingdom, there is a certain general, though irregular, relation 

 between the initial and the final bulks. Vegetals 



exhibit this relation less manifestly than animals. Yet 

 though, among the plants that begin life as minute spores, 

 there are some which, by the aid of an intermediate form, 

 grow to large sizes, the immense majority of them remain 

 small. While, conversely, the great Monocotyledons and 

 Dicotyledons, when thrown off from their parents, have 

 already the formed organs of young plants, to which are 

 attached stores of highly nutritive matter. That is to say, 

 where the young plant consists merely of a centre of deve- 

 lopment, the ultimate growth is commonly insignificant; 

 but where the growth is to become great, there exists to 

 start with, a developed embryo and a stock of assimilable 

 matter. Throughout the animal kingdom this rela- 



tion is tolerably manifest though by no means uniform. 

 Save among classes that escape the ordinary requirements of 

 animal life, small germs or eggs do not in most cases give 

 rise to bulky creatures. Where great bulk is to be reached, 

 the young proceeds from an egg of considerable bulk, or is 

 born of considerable bulk ready-organized and partially 

 active. In the class Fishes, or in such of them as are subject 



