300 w. j. c. boss. 



Notes on the Maps and Section. 

 Map No. 1, on a scale of two inches to the mile, is intended to 

 indicate the principal geological features of the country between 

 Bathurst and Limekilns. The topographical details have been 

 inserted mainly from the parish maps. The geological lines are 

 drawn from my own observations and are subject to correction 

 after further work, especially as to the limits of the Silurian and 

 Devonian about the head of Clear Creek — a rather rough country 

 which I have not yet examined carefully. 



The section along the line A B (Plate 42) is on a horizontal scale 

 three times that of the map. The vertical scale is about one inch 

 to two hundred feet. The heights are reckoned from the level of 

 Bathurst, as a datum line, but it is not shaded below the level 

 of Cheshire Creek, since it is impossible to predict with any 

 confidence the arrangement of the rocks at a distance from the 

 surface. No doubt the granite underlies the area, but at what 

 depth one cannot say. The line of juncture between the granite 

 and Silurian varies much around Bathurst. Thus, on the Lime- 

 kilns road it is about two hundred and fifty feet above, and on 

 Clear Creek, near Peel, about fifty feet below Bathurst ; while 

 on the Sydney road the granite appears at about seven hundred 

 feet above Bathurst, near Yetholm. 



List of Specimens. 

 No. Locality. Description. 



Fernbrook ... ... Polished slab, to illustrate the character 



of the stone. 



1. Fernbrook ... ... Section of Cephalopod, probably Gom- 



phoceras. 



2. ,, ... ... Section of Cephalopoda. Orthoceras, 



Gomphoceras, and, possibly, Ormo- 

 ceras present. 



3. „ ... ... Section of Cephalopoda. Orthoceras^ 



possibly Cyrtoceras. 



4. ,, ... ... Section, part of large Cephalopod. 



