326 NATURAL SCIENCE [November 



series of pages, imseparated by gaps, dislocations, and unconforma- 

 bilities, and this in the marine series just as much as in the sub- 

 aerial series. 



There are two initial lessons, then, I wish to press home before 

 I venture on to more concrete lessons, namely : — 1. That our pre- 

 sent system of geological arrangement and nomenclature is only 

 adapted to the purely local sequence of facts and history of the beds 

 of Western Europe, and not to the whole world. 2. That we 

 ought to arrange our beds on a universal and ideal system in two 

 perfectly continuous series, one marine and one sub-aerial, marked 

 not by their superposition in any one spot, but by the successive 

 changes in the biological history of the world, and by no other test. 



Henry H. Howorth. 



