The Future of Geology. 345 



taken in their totality, imprinted a recognisable fades on each as- 

 semblage of organisms — on the population of the earth and sea during 

 successive epochs or groups of ages. When a paleontologist is shewn 

 a number of unknown fossils from a distant and unexplored country, 

 he recognises almost instinctively an aspect in the collection which 

 induces him to declare them, with little hesitation, to be palaeozoic, 

 or oolitic, or whatever the term may be. The pure geologist seizes 

 with avidity on this determination, and assigns to the rocks from 

 whence the specimens have been obtained a definite position in his 

 scale of formations. If the naturalist recognise a previously deter- 

 mined species, his colleague is the more certain of his decision, and 

 from the shell or plant, or coral, that is known, decides upon the 

 age of the rock and region that are unknown. Nevertheless, it is 

 more than questionable whether identity of species in two or more 

 very distant localities should imply synchronism of age of the strata 

 wherein they occur ; indeed, it is less than improbable that the in- 

 ference drawn from the fact should be exactly the reverse. If so, 

 what becomes of the hard horizontal lines drawn on our tables and 

 diagrams between systems and formations ? They have been as- 

 sumed, it is true, from the consideration of facts — but facts of a local 

 character, and important only in connection with limited regions. In 

 reality we are often endeavouring to apply a scale which, in its sub- 

 divisions, is true only in Britain and part of Europe, to the whole 

 world. The procrustean operation has been too often performed by 

 geologists. 



Regarding, then, the geological scale of formations as an artificial 

 scheme, founded on local considerations, although an instrument and 

 standard of comparison of great value when used judiciously, the 

 questions have still to be answered, which demand whether the terms 

 of its graduation be required, and whether, such as we have them, 

 they are complete. There are reasons for believing that they are 

 far from being so, and that future research will intercalate many 

 unrecognised stages. 



See those broad stripes of demarcation painted on every geological 

 diagram between the terms palaeozoic and secondary, secondary and 

 tertiary. Those lines are popularly understood to mark the boundaries 

 between a complete cessation of one great system of types of species, 

 and the commencement of an entirely new series of creatures, animal 

 and vegetable. They really mark prodigious gaps in our knowledge 

 of the sequence of formations and the procession of life. One of 

 those supposed impassable barriers or boundaries, that between 

 «{ tertiary" and "cretaceous," threatens rapidly to give way, and to 

 vanish in due time as speedily as artificial social distinctions in society. 

 In France, in Germany, in Belgium, in England, there are symptoms 

 of an intergrowth between the long-separated " chalk" and " eocene." 

 Strata are coming to light which rudely insist on finding elbow- 

 room among our neatly-packed systems and formations. Janus-like 



