178 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 8, 



Serpula, sp. ' j Wood. 



Crustacean remains. 



, Among the Oxfordian fossils obtained from the drifts of Elgin- 

 shire and the adjoining counties there occur many very interesting 

 and not a few new forms. Among these may be especially men- 

 tioned several beautiful species of Placunopsis. 



The clay of Blackpots, near Banff, yields a number of Oxfordian 

 fossils, such as Gryphcea dilatata, Sow., Belemnites Owenii, Pratt, and 

 Belemnites abbreviatus, Mill. ; but with these are mingled Upper- 

 Oolite forms like Ammonites mutabilis, Sow., Lima concentrica, Sow., 

 and many others, The clay here is certainly a drift deposit, as was 

 shown by Mr. Prestwich* and Hugh Miller f, and not a mass of 

 Oolite in situ, as it had previously been considered. 



§ 8. The Upper Oolite. 



The Upper Oolites, which are now for the first time recognized as 

 existing in the northern part of this island, are represented by a great 

 series of strata of shales, sandstones, and grits, the whole of which 

 indicate the prevalence of littoral and estuarine conditions during 

 their deposition. They attain to a thickness of probably not less than 

 1000 feet, and yield a splendid fauna and flora. 

 . The base of the Upper Oolites is, so far as I know, exposed only 

 at one point in Sutherland, namely the vicinity of Braamberry 

 Hill. At this place, unfortunately, the quarries which formerly ex- 

 isted are now all closed. Above the beds of limestone, already 

 noticed as representing the Coralline Oolite, are some white sand- 

 stones with marine shells, including Ammonites biplex, Sow., and 

 some other species. I have been able to examine a few fossils which 

 have been preserved from a quarry in these beds near Clynlish ; and 

 although the question is not placed altogether beyond doubt by them, 

 yet the balance of evidence is decidedly in favour of our consider- 

 ing them as belonging to the Upper, rather, than to the Middle, 

 Oolites, 



Above these marine sandstones are others without fossils, and 

 probably of estuarine origin, which contain some beds of clay, and 

 bands with much carbonaceous matter. These strata are very im- 

 perfectly exposed. Perhaps the beds seen to be so curiously con- 

 torted in the dyne-Kirk gorge (see fig. 2, page 118), where they are 

 faulted against the Silurian rocks, belong to this part of the series. 

 The-upper part of the sandstones is exhibited north of Allt-na-cuil, 

 where, the strata being bent in opposite directions, the rocks in ques- 

 tion are the lowest exposed, and form the apex of a great anticlinal 

 fold. 



These unfossiliferous sandstones are succeeded by others contain- 

 taining scattered quartz pebbles, and sometimes passing into a very 

 coarse grit or conglomerate ; the latter are often crowded with 

 casts of marine fossils, which, however, are usually very imperfectly 

 preserved. Masses of wood, also in the condition of casts, and often of 



* Proc. Geol. Soc. vol. ii. p. 545. • t Kambles of a Geologist, 1858. 



