2i8 THE WALKS ABROAD OF 



few hundredths of a millimetre in diameter, there 

 being 2,500 one-hundredths of a millimetre in a single 

 inch. 



" Many live after the fashion of parasites ; almost 

 all, if not actually all, aquatic plants are covered 



FORAMIXIFEBA, GREATLY MAGNIFIED. 



with them. A simple washing with sulphuric acid is 

 generally sufficient to detach them. And, just as if 

 they were nevertheless in difficulty to find room, 

 these microscopic beings actually take lodgings in the 

 stomachs and on the scales of fishes. 



