364 Reviews — Barrande's Cephalopoda of Bohemia. 



a remarkable stability in the generic characters, in the specific 

 distinctions and in the elements which form the shell of molluscs of 

 this order. " The theory of evolution of the Cephalapods, like that 

 of the Trilobites, appears to us to be a mere product of the imagination 

 without any foundation in fact." 



We have given M. Barrande's conclusions with all their force, 

 though necessarily without the detail of argument which he has 

 brought to their support. We cannot follow him in this detail, but 

 "we must suggest great caution in admitting as ' proven ' all that is 

 assumed as such in this brochure. For instance, in his general 

 conclusions, he starts by recalling two predominant facts, so pre- 

 dominant in truth as to rule everything else. Now the first of these 

 is the absence of Cephalopods in the primordial Silurian fauna. It 

 may be, and we admit that M. Barrande has fully and fairly quoted 

 the evidence, that no Cephalopod has as yet been recognized in this 

 fauna. But he would be indeed a bold man who, therefore, would 

 assert that no Cephalopod existed. Is there not in this, as in so 

 much so-called Geological reasoning, a little suspicion of what a 

 logician would call " arguing in a circle " ? Has the " primordial " 

 age of the several groups been determined on evidence altogether 

 independent of such considerations of fossil data ? Has not the 

 belief in this supposed absence of Cephalopods from the earlier 

 stages been sufficient to determine at once, that any beds in which 

 they were found could not be of that epoch ? Has there always 

 been sufficient care, and sufficient detail given to analysis of the 

 accompanying facts ? In any case, the attempt to base such import- 

 ant and widely influential conclusions on what is confessedly purely 

 negative evidence (if there can be such), is fraught with danger, 

 and is to be most jealously guarded. And a reference to M, Barrande's 

 details shows in how very many particulars he has no other evidence 

 to rely upon. 



We rejoice to think that he has been enabled to complete this 

 magnificent contribution to Palasontology, and we trust sincerely he 

 may yet be spared to carry out the intentions which he announces 

 as now in progress — the rapid issue of more than 120 plates of the 

 PalEeozoic Gasteropoda, and of 114 plates of Brachiopoda (all ready 

 printed), besides a very large series of the Acephala. In common 

 with every palaeontologist, we look with anxious longing for these 

 valuable contributions to the literature of our science ; and whether 

 the progress of his investigation may lead to the confirmation of his 

 present views as to the illusionary nature of any theories of evolution, 

 or may tend to modify these, we know that we shall have from 

 M. Barrande what is beyond all theory in value, — the carefully 

 worked out, and carefully thought out expression of his honest 

 opinions. We most heartily congratulate him on the completion of 

 the Cephalopods, and wish him every success in the further prose- 

 cution of his labours. T. Oldham. 



