48 GEOLOGY. 



be more developed in the lower portion of the lower green sand belt. This, however, is a mere 

 suggestion to point only to the regions where data may he sought for ; by means of which the 

 distribution and limits of an eocene, and, perhaps, even pleistocene formation could be recog- 

 nized. 



We had not the opportunity to make such an investigation. It therefore devolves on some 

 other person to continue the researches necessary to a complete understanding of the subject, 

 and to the advancement of science in ge-neral. 



