CXVm PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



breathed life into those creatures which dwelt in the oldest palaeozoic 

 ages. Organic life on this earth must have had a beginning, and 

 that beginning must have proceeded from a source very different 

 from that dead matter which formed the visible body ; and from 

 that same source proceeded the principle of vitality which animated 

 the new forms when successively created on the earth. And with 

 reference to this question, I must emphatically deny the right 

 assumed by Prof. Powell, when he puts what he calls an imaginary 

 case of a truly new species making its appearance, to question those 

 who deny the theory of transmutation, how this new species made 

 its appearance ; whether it appeared as an ovum or seed, or at what 

 period of growth, &c. "When Prof. Powell can state in what form 

 the first living organisms appeared on the earth's surface, he may 

 demand an answer to this question. It is the more remarkable 

 that Prof. Powell should make this demand, as he has stated, in 

 a former part of the Essay, that in a geological point of view the 

 term "Creation" signifies the fact of origination of a particular 

 form of animal or vegetable life, without implying anything as to 

 the precise mode of such origination : not that I think this definition 

 altogether satisfactory, but yet it might have precluded him from 

 making such a demand. 



But I have been led into a longer statement than I had intended. 

 I will merely add that, notwithstanding these criticisms that I have 

 ventured on, the essays of Prof. Powell deserve a careful and atten- 

 tive reading. They are eminently suggestive and replete with deep 

 thoughts and scientific views, and form an interesting element of the 

 geological, or rather geognostic, literature of the day. 



As in some measure connected with the same subject, I must 

 direct your attention to a paper published by Mr. Alfred Wallace * 

 on the law which has regulated the introduction of new species. Mr. 

 "Wallace is a naturalist of no ordinary calibre. His travels in South 

 America and elsewhere are a sufficient guarantee of his high merits ; 

 he now writes from Sarawak, Borneo. From a careful examination 

 of the actual distribution of existing forms of animal life, and the 

 gradual but complete renewal of the forms of life in successive geo- 

 logical epochs, he has deduced the following law : — Every species 

 has come into existence coincident both in space and time with a 

 prc'-existing closely allied species. The question is one of great 

 importance, and deserving the careful investigation of every geologist ; 

 but I think it may be doubted whether this assumed law can be 

 maintained as a universal generalization. 



Gentlemen, — Having thus, however imperfectly, gone through 

 my allotted task, it only remains for me, before quitting this Chair, 

 to thank you for the forbearance you have shown to my shortcomings, 

 and to entreat your indulgence for what I may have neglected during 

 the period I have had the honour of presiding over t-his Society. I 

 know that there are many who might have brought more varied in- 

 formation and geological knowledge to bear on the discussions at our 

 * Ann. of Nat. Hist. vol. xvi. p. 104. 



