53 



ing species of Corals, the Jurassic age must indeed have been one of long 

 duration ; for example, it has been calculated that the recent coral formations 

 in the gulf of Florida, measured by the time ascertained to have been occupied 

 in the growth of individual species of Cofal now living in the gulf, could not 

 have been less than seventy thousand years. The inner reef on the land and 

 the outer reef in the water having been constructed by the same species of 

 Polypifera. This is a subject of great interest, and opens up to naturalists a new 

 field of investigation. Perhaps the wonderful subject of Geological time will 

 receive some important elucidation when we come to study more in detail the 

 history of the Jurassic formations, viewed in connection with the Coralline 

 structures that enter so largely in the natural history of this group of rocks. 



It is impossible, without the aid of pictorial illustrations, to make this 

 subject clear in an after-dinner speech, nor woxild it now have been introduced 

 at all, had not my learned friend, your esteemed President, pressed me to make 

 a few passing remarks upon a subject which he knows has occupied my attention 

 for some time past (applause). 



