144 HIDDEN BEAUTIES OF NATURE 



are each the hundredth of an inch in diameter ! The 

 next two are smaller ; their diameters are only the 

 hundred and twenty-fifth of an inch, while the last, 

 amphora, a name it well deserves, is the hundredth 

 of an inch. All but the last on the bottom row are 

 each only the two hundredth, and the last the two 

 hundred and fiftieth of an inch. Grains of trans- 

 parent quartz sand make up the shells of nine of 

 these figures. That of the first is quartz sand mixed 

 with diatom cases (see chapter on Diatoms). The 

 shell of the eleventh is made up entirely of diatoms, 

 while that of the twelfth is entirely composed of 

 pellets of clay. Here are vases, water-bottles, gipsy 

 crocks and amphoras, so small that we require a 

 microscope in order to see their beauty. 



Let any student of practical geometry take his 

 compasses and ivory scale and let him mark off on a 

 sheet of paper the dimensions of these vases, ranging 

 from the hundredth to the two hundred and fiftieth 

 of an inch, and show the spaces in which they could 

 be arranged, and it will dawn upon his mind that the 

 fashioning of these tiny homes is something beyond 

 our knowledge and power to fathom. 



We have observed that, so far, the shells of many 

 of the DifHugia are made up of substances exterior 

 to the creatures themselves, and are therefore 

 extrinsic. 



Dujardin in 1837, Ehrenberg in the following year, 

 also Carter and Dr. Wallich, studied and described 

 several forms of DifHugia. They found that the 



