IN THE MUD OF THE LEVANT. 61 



specimens which I examined, and for which I am 

 indebted to the kindness of the Marquis of 

 Northampton, by whom they were collected, are 

 chiefly from the limestone in the vicinity of 

 Palermo, connected with the tertiary formations 

 of Sicily.* Speaking of a portion of this deposit 

 at Spaccaforno, Mr. Lyell observes, that " it is, 

 for the most part, of a pure white, often very 

 thick bedded, and occasionally without any lines 

 of stratification. This hard white rock is often 

 four or five hundred feet in thickness, and 

 appears to contain no fossil shells. It has much 

 of the appearance of having been precipitated 

 from the waters of mineral springs, such as 

 frequently rise up at the bottom of the sea, in 

 the volcanic regions of the Mediterranean. As 

 these springs give out an equal quantity of 

 mineral matter at all seasons, they are much more 

 likely to give rise to unstratified masses than a 

 river which is swollen and charged with sedimen- 

 tary matter of different kinds and in unequal 

 quantities, at particular seasons of the year.f 



However this may apply to the deposit at 



* See Lyell's Principles. Vol. iii. p. 320. 

 t Lyell's Principles. "Vol. iii. p. 220. 



