54 ANIMAL INDIVIDUALITY [CH. 



molecule-population increases, the demand of each 

 molecule is no less, but, owing to the disproportion 

 between surface and volume, the supply available for 

 each is dwindling. The actual materials of supply 

 still exist in unlimited quantity, but the organism 

 cannot get at them. If the English Nation, with 

 population advancing by leaps and bounds, were not 

 able to build harbours and provide dock-labourers as 

 quick as she bred men, all the wheat in Canada, with 

 Imperial Preference to help, would not keep her from 

 starvation, for the simple reason that it could not 

 get in. 



So the primeval drop of protoplasm, earliest 

 ancestor of all living organisms, the English Nation 

 not forgotten, found, as it grew, its ports and landing 

 facilities not keeping pace with the demands upon 

 them. Each particle of food and oxygen has to be 

 handled by the surface molecules unloaded from the 

 circumambient water, loaded up again into solution in 

 the general protoplasm before the central populace 

 can feed or work ; and for each four-fold increase of 

 the transport workers there is a sixteen-fold increase 

 within of the mouths to be fed. This cannot go on 

 indefinitely : but what is to be done ? 



There are two alternatives. One is for the mass 

 of protoplasm to continue its growth, but obviate the 

 difficulty by spreading itself out in one plane. In 

 such a film of uniform thickness, whatever its extent, 



