506 



Dr. W. B. Carpentel* on the Structure [May 16, 



by distinct traces, in other parts of tlie same formatiou, of organisms 

 adei^uate to its production. The Carboniferous Limestone, various mem- 

 bers of the Oolitic and Cretaceous formations, and the Hippurite and 

 Nummulitic Limestones, all exhibit in parts an entire absence of organic 

 structure, which is yet so distinct elsewhere, as to justify the generali- 

 zation that their materials have been originally separated from the 

 ocean-waters by animal agency. And it is well known to those who 

 have studied the changes which recent Coral-formations have undergone 

 when upraised above the sea-level, that a complete conversion of a mass 

 of Coral into a sub-crystalline Limestone not distinguishable from 

 ordinary Carboniferous Limestone, may take place under circumstances 

 in no way extraordinary. 



It is, therefore, upon the character of the Serpentine-Limestone of 

 Canada, not upon the nature of the Connemara Marble, that the ques- 

 tion of organic origin entirely turns ; and, as I have elsewhere shown 

 in detail*, the hypothesis of Professors King and Eowney altogether 

 fails to account for the comhinatioii of phenomena which the former 

 presents, whilst the accordance of that combination with the idea of its 

 Organic origin (a very moderate allowance being made for the effects of 

 metamorphic change) is such as to establish the same kind of pro- 

 bability in its favour, as that which we derive in the case of the Human 

 origin of the " flint implements " from the cumulative evidence of their 

 succession of fractured surfaces, or in the case of the chemical compo- 

 sition of the sun from the precise correspondence between certain dark 

 lines in the solar spectrum and groups of bright lines produced in a dark 

 spectrum by the combustion of certain known metals. 



I may stop to point out, however, that Professors King and Eowney 

 do not attempt to offer any feasible explanation of the fundamental fact 

 of the regular alternation of lamellsB of Calcareous and Siliceous minerals, 

 often amountiug to fifty or more of each kind, extending through a 

 great range of area ; nor of the fact that not only is this arrangement the 

 same, though the siliceous mineral may be Serpentine in one place. 

 Pyroxene in another, or Loganite in another, whilst the calcareous may 

 be Calcite in one part, and Dolomite in another, — but that these varia- 

 tions may occur in one and the same specimen, the structural arrange- 

 ment being continuous throughout. 



And in what they state of the peculiar lamella forming the proper 

 wall of the chambers, which I have designated the " nummuline layer," 

 they have fallen into errors of fact so remarkable, that I can only ac- 

 count for them by the belief that when their paper was written they 

 knew this layer only by decalcified specimens, and had never seen it in 

 thin transparent sections. Por they describe it as composed of parallel 

 fibres of chrysotile packed together without any intermediate sub- 

 stance ; whereas I have distinctly j^roved that the siliceous fibres are im- 

 Quarterly Journal of the Geological Society, August, 1866. 



