STRUCTURE OF LIVING THINGS 173 



the Royal Society, published a beautiful book of folio 

 size, entitled Micrographia. In this he pictured various 

 minute insects and various natural products as seen 

 under his microscope. Among the objects figured and 

 described was a piece of cork (Fig. 38). Hook showed 

 that it was built up of a number of empty, air-holding, 

 box-like chambers, less than the hundredth of an inch 

 in length, and these he called " cells," comparing them 

 to the " cells " of the bee's honeycomb. Later observers 



FIG. 38. Copy of part of Robert Hook's drawing of a magnified 

 piece of cork, showing the "cells " so named by him in 1665. 



found that this " cellular " structure was very common in 

 plants but it was not until more than a hundred years 

 later that it was observed that the " cells " which build 

 up the soft stems and leaves of plants are not empty or 

 merely air-holding, but contain a liquid or viscid matter. 

 Robert Browne, a great botanist, who lived within the 

 memory of some of our older naturalists, first observed and 

 described the " nucleus," or kernel, within the cells of some 

 lily-like plants, and gave it that name (Fig 37 A, d}. 

 About the thirties of last century, by aid of improved 



