OPTIMISTIC OUTLOOK 93 



was not of the easily fossilizing type. Also, rocks of such great age 

 are generally either rendered almost unrecognizable through meta- 

 morphism, or buried by younger rocks. Geologic study of the old 

 shields is, however, rapidly expanding. Hence, it is really not too 

 optimistic to expect that much further information on this subject 

 will turn up in the near future; nor is it too optimistic to hope for 

 as large a stride forward to be taken during the coming decades, as 

 has been taken during the last two. 



