48 FOSSIL RADIOLARIA 



Jaspers and Whetstones in the Hartz and the Ural 

 Mountains. 



Triassic rocks of Hungary. 



Liassic rocks of Hanover and the Tyrol. 



Jurassic rocks of Italy and Hungary. 



Coast ranges of South California. 



Cretaceous rocks of Westphalia and Manitoba. 



From this extensive list it will be seen that 

 the Kadiolaria, with all their beauty of form, 

 are as old as most forms of life, and that their 

 history runs parallel with that of most of the 

 massive land and marine creatures of several 

 successive geological epochs. 



They form the chief constituent in the com- 

 position of the jasper, chert, and hornstone 

 of vast extent in the Mesozoic and Palaeozoic 

 rocks. In fact these rocks, however intensely 

 hard they may appear, are mainly formed of 

 Kadiolarian skeletons. By making thin micro- 

 scopic sections these organisms may be seen 

 distinctly. 



Greater satisfaction will, however, be secured 

 by submitting a sample of Barbadian rock to 

 the following process : 



< Crush the rock and boil it in a strong solu- 



