GEOLOGY OF THE KEMPSEY DISTRICT. 167 



Stratigraphically below the limestone, and undoubtedly 

 conformable with them there is an immense series of 

 greenish tuffs and tuffaceous slates, considerably contorted 

 and faulted, so that its exact thickness cannot be estimated 

 at present. This series is closely similar in lithological 

 character to the sub-glacial tuff of the Macleay River, and 

 I feel quite confident as to the identity of the two form- 

 ations. A very important fact is that certain horizons (or 

 a certain horizon) in the Manning area is richly fossiliferous. 

 In the railway ballast quarry at the Devil's Slbow (about 

 five miles along the line from Taree towards Wingham) 

 there is exposed a massive bed of greenish tuff which con- 

 tains abundant casts of Pachydomus, which Mr. Dun recog- 

 nises as being very similar to a form occurring in the 

 Gympie Series at Gympie in Queensland. Very numerous 

 specimens of this fossil are to be obtained from the railway 

 ballast derived from this quarry. What is probably the 

 same bed occurs in a railway cutting west of Kiliwarra 

 Railway Station, and here again Pachydomus is abundant. 

 If these two occurrences are parts of one bed it should 

 provide a most useful persistent horizon in geologically 

 mapping the district. 



The discovery of this fossil determines the age of the 

 beds as Permo-Carboniferous, and, taken in conjunction 

 with the evidence of the Macleay beds, indicates a vast 

 thickness of subglacial beds of that age. A comparison of 

 the lithological characters of this subglacial tuffaceous 

 series, with those of the gold bearing rocks of Gympie itself, 

 shows a very striking similarity between the two form- 

 ations, and I venture to suggest that we may tentatively 

 assume, as a working hypothesis, that the Gympie System 

 of the Queensland geologists includes the subglacial por- 

 tions of the Manning and Macleay beds. If this is so, a 

 detailed survey of the areas described in this note is likely 



