x.J GEOLOGICAL CONTEMPORANEITY. 213 



the moment the geologist has to deal with large areas, 

 or with completely separated deposits, the mischief 

 of confounding that " homo taxis " or 4i similarity of 

 arrangement," which can be demonstrated, with " syn- 

 chrony" or "identity of date," for which there is not 

 a shadow of proof, under the one common term of 

 ' contemporaneity " becomes incalculable, and proves 

 the constant source of gratuitous speculations. 



For anything that geology or palaeontology are able 

 to show to the contrary, a Devonian fauna and flora 

 in the British Islands may have been contemporaneous 

 with Silurian life in North America, and with a Car- 

 boniferous fauna and flora in Africa. Geographical pro- 

 vinces and zones may have been as distinctly marked in 

 the Palaeozoic epoch as at present, and those seemingly 

 sudden appearances of new genera and species, which we 

 ascribe to new creation, may be simple results of migration. 



It may be so ; it may be otherwise. In the present 

 condition of our knowledge and of our methods, one 

 verdict — "not proven, and not proveable" — must be 

 recorded against all the grand hypotheses of the palaeon- 

 tologist respecting the general succession of life on the 

 globe. The order and nature of terrestrial life, as a 

 whole, are open questions. Geology at present provides 

 us with most valuable topographical records, but she 

 has not the means of working them into a universal 

 history. Is such a universal history, then, to be regarded 

 as unattainable ? Are all the grandest and most in- 

 teresting jDroblems which offer themselves to the 

 geological student essentially insoluble \ Is he in the 

 position of a scientific Tantalus — doomed always to 

 thirst for a knowledge which he cannot obtain ? The 

 reverse is to be hoped ; nay, it may not be impossible 

 to indicate the source whence help will come. 



In commencing these remarks, mention was made of 



