180 PKOCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 8, 



Lothbeg river now flows to the sea, and in the adjoining railway- 

 cutting, the shales contain a few marine fossils crushed between the 

 laminae. These are as follows : — 



Ammonites alternans, Von Buck. 



« flexuosus, Miinst. 



biplex, Sow. 



Belemnites obeliscus, Phil. 



spicularis, Phil. 



Lima eoncentrica, Sow., &c. 



The Belemnites are nearly always fragmentary. Thus the series 

 of estuarine beds just described graduates up into the marine strata 

 above them. 



At the cliff between Lothbeg River and Lothbeg Point the beds 

 just described are seen to underlie and pass up into a set of hard 

 sandstones and grits, alternating with finely laminated black shales. 

 These beds, together with the limestones, with which in their upper 

 part they alternate, were referred by Sir Roderick Murchison to the 

 Lower Oolites, on account of the resemblance of some of the beds to 

 the Forest-marble and Cornbrash of the south of England, though but 

 very slight paleeontological evidence was adduced in support of this 

 correlation. The resemblance of some of these beds, in their mineral 

 characters, to the English Forest-marble is certainly sufficiently 

 marked ; but this must be regarded as the result only of the simi- 

 larity of conditions under which the two sets of beds were deposited — 

 the broken condition of the shells, the abundance of wood and 

 plant-remains, and the prevalence of certain genera of Mollusca in- 

 dicating that in both cases the strata were deposited under littoral 

 conditions. The fauna of these beds, however, like that of the ma- 

 rine sandstones several hundred feet below, yields unmistakable 

 evidence that the whole of these strata, with the estuarine clays 

 and sands between them, must be referred to the Upper Oolite. 



This series of grits, shales, and limestones, which can be traced 

 at the mouths of several small ravines at Achrimsdale, Clyne-Mill- 

 town, and just north of Kintradwell, is admirably exposed, for a 

 distance of 11 miles, in reefs on the shore, and also in some inland 

 sections, at a v great number of points between Kintradwell and Green- 

 Table Point, and even northward in the county of Caithness. Bent 

 into innumerable folds and broken up by many faults, as already de- 

 scribed, the beds of this series are repeated again and again along 

 the shore by Garty, Port Gower, Helmsdale, and Navidale. Owing 

 to the superior hardness of the grit-beds of the series, these strata 

 have resisted denudation, and form a number of small headlands, 

 terminating in long reefs of rocks. As already described, these beds 

 are singularly crumpled and broken. The softer shales and inter- 

 bedded sandstone laminae have in a great measure yielded to the 

 forces to which they have been subjected ; and where they have been 

 planed away many beautiful examples of waved and contorted 

 stratification, accompanied by small hitches or faults, are exhibited 

 with all the clearness and distinctness of a geological diagram. The 

 brittle sandstones, on the other hand, have by the same forces been 

 crushed and broken into fragments ; and angular masses of the harder 

 portions of them lie in the greatest confusion, imbedded in a matrix 



