372 THE RELATIONS OF GEOLOGY. 



been to a large extent replaced in clearer and more comprehensive schemes; and we 

 are enabled to-day to deduce with an accuracy proportionate to our increased knowl- 

 edge of fact the nature of the interrelationships of the living beings, which with 

 ourselves inhabit the earth. * * * Satisfactory as is the result, it must be clearly 

 borne in mind that its realization coidd not have come about but for a knowledge of 

 the animals of the past. 



It is at the present daj" the ha))it of some to hint that pah^ontology, 

 as geologists understand it, is a mere l)ranch of hiology, just as it 

 was the fashion half a centiiiy ago to look upon it as a branch of 

 geology. But the proper view, 1 take it, is to regard it as the common 

 possession of ])otli these sciences. Here, as in so man}' contests of 

 opinion, the truth lies in the middle. It is undeniable that all the 

 organic remains discovered l»y the geologist were in their day mem- 

 bers of the great biological chain of life, and have, therefore, their indi- 

 vidual places and relationships in the scheme of biological classification; 

 and that as a consequence the study of their structure and their rela- 

 tionships falls within the province of biology. But it is equalh' unde- 

 niable that each of these creatures had an existence during a definite 

 range of geological time, and that its fossilized remains occur at a 

 certain horizon in the ascending series of the geological formations. 

 They have thus a geological arrangement and grouping as inevitable 

 and necessary as the biological one. While we grant that the biolo- 

 gist has not only a right but almost an obligation to place in its sys- 

 tematic biological position in his museiun an example of everv species 

 hitherto discovered b}- the geologist, it is equally important for the 

 advancement of science in general that the geologist shall have in his 

 museum a stratigraphical grouping and chronological arrangement of 

 fossil species always available for his geological Avork. There is a 

 phylogenetic grouping by affinity for which the biologist is constantly 

 striving, and to which he is dail}^ more and more approximating; but 

 there is also a chronological grouping by geological position, which 

 for every individual specimen in the paleontological department of a 

 geological museum was practicallv fixed the day when that specimen 

 was collected from a known stratigraphical horizon. We ma}' rest 

 assured that 3'ear by 3'ear the stratigraphical classification in our 

 geological museum will l)ecome more detailed and more refined. 

 This chronological grouping constitutes a tool with which geology can 

 not possibly dispense. Again and again in the years gone by the 

 apparent sequence and the known paleontc^logy have been in conflict 

 as to the true stratigraphical position of local formations, and in every 

 known case hitherto the paleontological side has scored the victory. 



But, indeed, if we geologists were ever to become so benighted as to 

 neglect this detailed sequential classification of the fossils in our 

 museums, the biologists themselves would soon force it upon us for 

 the sake of their own science. Fossils as thus arranged are and can 

 be the only tangible proofs of the chronological order in which the 



