"274 ON THE PARTICULAR ORDER OF 



in the same country. Similar deficiencies have been 

 observed in many other countries ; so that this is not 

 an indispensable stratum. 



The limestone which follows it, when present, called 

 in England, the mountain, and the carboniferous lime- 

 stone, and which seems to have been generally con- 

 sidered as a transition limestone on the continent of 

 Europe, is also occasionally wanting altogether. In 

 Scotland, it is absent, not only in the cases just enu- 

 merated where the red sandstone is also deficient, but 

 even sometimes when that is present ; so that, in 

 many parts of the same country, the coal strata repose 

 immediately on this oldest secondary rock. If it 

 should prove true, as seems probable, that the upper 

 parts of the Arran sandstone belong to the red marl, 

 then both these, namely the lowest and highest red 

 sandstones, are in contact, and nearly confounded 

 together, in most places. I may pass over the coal 

 strata ; as, from their acknowledged partial and inde- 

 pendent nature, they do not form part of the present 

 inquiry. It may only be remarked, that such is the 

 irregularity of recurrence among the beds belonging 

 to this series, that in no two examples is that similar. 



Beyond this we arrive at the magnesian limestone 

 of the English series, supposed to correspond to the 

 first flcetz stratum, to the alpine limestone, and to 

 the zechstein of foreign geologists, and followed by 

 the later red sandstone, or red marl, agreeing with 

 their variegated sandstone. A new order of arrange- 

 ment here begins among the secondary strata, whence 

 we may take a fresh departure. It is not meant to 

 say, that the red marl, much less the associated infe- 

 rior limestone, is invariably present, even in Europe 

 where it is known to occur; but if there is any series 

 truly entitled to the character of regularity, as well as 



