174 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



[Jan. 8, 



stone." Masses of these rocks, in a decomposed condition, are found 

 in the Till at the top of the Hare-Hill Quarries. This bed of lime- 

 stone is crowded with fossils, specimens of the very large variety of 

 Gryphcea dilatata being very numerous ; Ostrea gregaria also occurs 

 in considerable abundance. Ammonites of the group of the Cordati, 

 especially Ammonites excavatus, Sow., A. vertebralis, Sow., and the 

 large compressed variety of A. cordatus, Sow., which becomes smooth 

 with age, occur abundantly in this bed. Belemnites are rare, B. ab- 

 breviate, Mill., being the only form collected. The genera Pecten, 

 Modiola, Cucullcea, Pholadomya, &c. are represented by a number 

 of species. This bed of limestone has been traced in the neighbour- 

 hood of Braamberry Hill for some distance ; and some lime-pita were 

 opened in it at this point. It may be necessary to mention that it 

 was formerly the custom in the Highland districts to open pits 

 wherever a small bed of limestone was found, and to burn the stone 

 with peats ; but the greater facilities of transport have caused the 

 total abandonment of this practice. 



The fossils of this limestone-bed are often much distorted by pres- 

 sure ; they are enumerated in the subjoined list. 



Fossils of the Argillaceous limestone on the left bank of the Brora 

 {Coralline Oolite). 



Belemnites abbreviates, Mill. 



, sp. 



Ammonites cordatus, Sow., var. 



vertebralis, Sow. 



excavatus, Sow. 



Lamberti, Sow. 



, sp. 



Aptyckus, sp. 

 Pholadomya simplex, Phil. 



, spec. nov. 



Myacites retusus, Phil., sp. 

 Anatina undulata, Sow., sp. 

 Gonioinya v-scripta, Sow., sp. 

 Thracia depressa, Sow., var. 

 Isocardia, sp. 

 Cardium, sp. 

 CucullEea, spec. nov. 

 Area scabrella, Big. § Sauv. (A. qua- 

 drisulcata?, Sow.). 



semula, Phil. 



, sp. 



Modiola bipartita, Sow. 



Modiola cuneata, Sovj., var. 

 Lima lceviuscula, Sow. 



concentrica, Sow. 



Pinna lanceolata, Sow. 



■ mitis, Phil. 



Avicula expansa, Phil. 

 Pecten lens, Sow. 



demissus, Phil. 



vimineus, Sow. 



vagans, Sow. 



subfibrosus, Sow. 



• S P- . . 



Placunopsis inasqualis, Phil., sp. 



, spec. nov. 



Gryphtea dilatata, Sow., var. 

 Ostrea Eoemeri, Queiist. 



gregaria, Sow. 



Ehynchonella varians, ? Sow. 

 Serpula, sp. 



Fronds of ferns and other plant-re- 

 mains. 

 Wood. 



The limestones just described are covered by beds of clay, which, 

 on the left bank of the Brora, appear to be thrown out by a fault, so 

 that only a small portion of their thickness is seen ; but on the right 

 bank of the river they are well exposed and can be examined behind 

 the curing-house, where the bank has been cut back to make room 

 for the buildings. The beds seen here consist of dark-blue, more 

 or less pyritous, sandy clay, with a few small septaria. Some por- 

 tions of these clay-beds become extremely arenaceous, and are in- 



