ADDRESS. 19 



fact, coincident with tlic intelligence and education of the world. Several 

 commnnications connected with these problems will be broufrht before 

 the sectional meetings during the next few days, and we shall have the 

 advantage of hearing them discussed by some of those who by virtue of 

 their special attention to and full knowledge of these subjects are most 

 competent to speak with authority. It is therefore for me rather delicate 

 ground to tread upon, especially at the close of a discourse mainly devoted 

 to another question. I will, however, briefly point out the nature of the 

 problems and the lines which the endeavour to solve them will probably 

 take, without attempting to anticipate the details which you will doubt- 

 less hear most fully and ably stated elsewhere. 



I think I may safely premise that few, if any, original workers at any 

 branch of biology appear now to entertain serious doubt about the general 

 truth of the doctrine that all existing forms of life have been derived 

 from other forms by a natural process of descent with modification, and 

 it is generally acknowledged that to the records of the past history of 

 life upon the earth we must look for the actual confirmation of the truth 

 of a doctrine which accords so strongly with all we know of the present 

 history of living beings. 



Professor Huxley wrote in 1875 : ' The only perfectly safe foundation 

 for the doctrine of evolution lies in the historical, or rather archreological, 

 evidence that particular organisms have arisen by the gradual modifica- 

 tion of their predecessors, which is furnished by fossil remains. That 

 evidence is daily increasing in amount and in weight, and it is to be 

 hoped that the comparisons of the actual pedigree of these organisms with 

 the phenomena of their development may furnish some criterion by which 

 the validity of phylogenic conclusions deduced from the facts of embryo- 

 logy alone may be satisfactorily tested.' 



PalfBontology, however, as we all know, reveals her secrets with no 

 open hand. How can we be reminded of this more forcibly than by the 

 discovery announced scarcely three months ago by Professor Marsh of 

 numerous mammalian remains from formations of the Cretaceous period, 

 the absence of which had so long been a source of difficulty to all zoolo- 

 gists ? What vistas does this discovery open of future possibilities, and 

 •what thorough discredit, if any were needed, docs it tlii-ow on the value 

 of negative evidence in such matters ! Bearing fully in mind the neces- 

 sary imperfection of the record we have to deal with, I think that no 

 one taking an impartial survey of the recent progress of pala2ontologIcal 

 discovery can doubt that the evidence in favour of a gradual modification 

 of living forms is still steadily increasing. Any regular progressive series 

 of changes of structure coinciding with changes in time can of course 

 only be expected to be preserved and to come again before our eyes 

 nnder such a favourable combination of circumstances as must bo of 

 most rare occurrence ; but the links, more or less perfect, of many snoh 

 series are continually being revealed, and the discovery of a single intcr- 



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