50 FOSSIL RADIOLARIA 



both books are thoroughly understood, the more 

 they will be found to harmonise. 



I recommend the polycystina to all grades 

 of thinkers, to scholars of every school of re- 

 search, to divines, to philosophers, to teachers 

 of youth, to leaders of thought, with the full 

 confidence that the study of these almost in- 

 visible relics of life will impress their minds 

 with the grandeur of Nature, the marvels of 

 geology, the possibilities and the potentialities 

 of mere specks of flint. And their influence 

 is not likely to end even there. 



With regard to the first illustration of 

 Polycystina (Fig. 1, frontispiece), the original 

 photo-micrograph had an amplitude of 40 

 diameters. The exposure was three minutes 

 in sunshine. The second illustration (Fig. 9) 

 is from a photograph of 175 diameters. It was 

 also produced in sunshine, with an exposure 

 of eight minutes. 



Foraminifera. 



Under the microscope these shells, whether 

 recent or fossil, are always objects of great 



