74 REPORT — 1873. 



under critical inversions. These adaptations, so necessary to tlie preservation of a 

 race, are they restricted within narrow limits ? or is it possible that in the course of 

 long-endiu'ing time, step by step and grain by grain, one form of life can be 

 changed and has been changed to another, and adapted to fulfil quite different 

 functions ? Is it thus that the innumerable forms of plants and animals have been 

 " developed " in the course of ages upon ages from a few original types ? 



This question of development might be safely left to the prudent researches of 

 Physiology and Anatomy, were it not the case that Palseontology furnishes a vast 

 range of evidence on the real succession in time of organic structures, which on the 

 whole indicate more and more variety and adaptation, and in certain aspects a 

 growing advance in the energies of life. Thus at first only invertebrate animals 

 appear in the catalogues of the inhabitants of tlie sea ; then fishes are added, and 

 reptiles and the higher vertebrata succeed ; man comes at last, to contemplate and 

 in some degree to govern the whole. 



The various hyjjothetical threads by which many good naturalists hoped to 

 unite the countless facts of biological change into an harmonious system have 

 culminated in Darwinism, which takes for its basis the facts already stated, and 

 proposes to explain the analogies of organic structures by reference to a common 

 origin, and their differences to small, mostly congenital, modifications which are 

 integrated in particular directions by external physical conditions, involving a 

 " struggle for existence." Geology is interested in the question of development, and 

 in the particular exposition of it by the great naturalist whose name it bears, be- 

 cause it alone po.ssesses the history of the development in time, and it is to incon- 

 ceivably long periods of time, and to the accumulated effect of small but almost 

 infinitely numerous changes in certain directions, that the full effect of the transfor- 

 mations is attributed. 



For us, therefore, at present it is to collect with fidelity the evidence which our 

 researches must certainly yield, to trace the relation of forms to time generally and 

 physical conditions locally, to determine the life-periods of species, genera, and 

 families in different regions, to consider the cases of temporary interruption and 

 occasional recurrence of races, and how far by uniting the results obtained in dif- 

 ferent regions the alleged " imperfection of the geological record " can be remedied. 



The share which the British Association has talcen in this great work of actually 

 reconstructing the broken forms of ancient life, of repeopliug tlie old land and older 

 sea, of mentally reviving, one may almost say, the long-forgotten past, is considerable, 

 and might with ad\'antage be increased. We ask, and wisely, from time to time, for 

 the combined labour of naturalists and geologists in the preparation of reports on 

 particular classes or families of fossil plants and animals, their true structure and 

 affinities, and their distribution in geological time and geographical space. Some 

 examples of this useful work will, I hope, be presented to this Meeting. Thus have 

 we obtained the aid of Agassiz and Owen, and have welcomed the labours of Forbes, 

 and Morris and Lycett, and Huxley, of Dawkins and Egerton, of Davidson, Duncan, 

 and Wright, of Williamson and Oarruthers and Woodward, and many other emi- 

 nent persons, whose valuable results have for the most part appeared in other volumes 

 than our own. 



Among these volumes let me in a special manner recall to your attention the price- 

 less gift to Geology which is annually offered by the Palseontographical Society, a 

 gift which might become even richer than it is, if the literary and scientific part of 

 our community were fortunate enough to know what a perpetual treasure they 

 might possess in return for a small annual tribute. The excellent example set and 

 the good work recorded in the Memoirs of the Society referred to have not been 

 without influence on foreign men of science. We shall soon have such Memoirs 

 from France and Italy, Switzerland and Germany, America and Australia ; and I 

 trust the effect of such generous rivalry will be to maintain and increase the 

 spirit of learned research and of original observation which it is our privilege and 

 our duty to foster, to stimulate, and to combine. 



On all the matters, indeed, which have now been brought to your thoughts the 

 one duty of geologists is to collect more and more accurate information ; the one 

 fault to be avoided is the supposition that our work is in any department complete. 

 We should speak modestly of what has been done ; for we have completed nothing, 



