290 



Mr Connell's Analysis of the 



Phosphate of Lime, with a little Fluoride of Calcium, 



50.94 



Carbonate of Lime, .... 



11.91 



Siliceous matter, .... 



33.10 



Water, ..... 



3.48 



Potash and Soda, . 



.47 



Bituminous Matter, .... 



.12 



Phosphate of Magnesia, Trace 





Animal Matter, Trace 





36.58 



100.02 



The most unexpected part of this analysis was the occurrence 

 of so large a proportion of siliceous matter. Judging from the 

 beautifully perfect appearance of these scales, presenting a lustre 

 as fine in all likelihood as they possessed when they clothed the 

 sides of the immense living tenants of the primeval waters, we are 

 naturally led to expect no great change in their nature. A little 

 reflection, however, will show us that as fish scales are known to 

 contain a good deal of perishable animal matter, in addition to 

 the more permanent animal earths, which enter into their com- 

 position, it is necessary that the place of this destructible matter 

 should be taken by something more durable, in order that the 

 original form may be preserved. This seems to be the origin of 

 the siliceous matter ; and, in proof of the justness of this view, it 

 need only be mentioned, that when the scales are acted on by 

 acids, the insoluble matter remains behind as a fine siliceous 

 skeleton, formed, there can be little doubt, by the infiltration of 

 dissolved siliceous matter which has gradually taken the place 

 of the decaying animal matter. The fossil scales, on this view, 

 ought to consist of the infiltrated matter, together with the ori- 

 ginal animal earths ; and tins is exactly what we find to be the 

 case ; and it so happens, that in the present instance we are 

 enabled to determine, with some degree of plausibility, that even 

 the relative proportions of the different constituents have been 

 to a considerable extent preserved. We luckily possess an ana- 

 lysis of the scales of the recent Lepisosteus, as well as of several 



