XXV111. ABSTRACT OF PROCEEDINGS. 



miles. Interesting fossils, especially the plant Spheno- 

 phyllum were exhibited from the sedimentary formations 

 of the district. The topography is peculiar and is deter- 

 mined by the differential erosion of dense sills and weaker 

 sediments, all folded and intruded by numerous dykes. 



The area mapped lies south and west of that already 

 described in the Proc. Linn. Soc. N.S.W. In this, as in the 

 more northern and eastern areas the Carboniferous is con- 

 formable to the Devonian. Evidence was also brought 

 forward to show the intrusive nature of the Tamworth tuffs. 



Monthly Meeting, 8 September, 1915. 

 Mr. R. H. Oambage, in the Chair. 

 Seven members and two visitors were present. 

 exhibits: 



1. Mr. W. N. Benson exhibited specimens illustrating 

 tertiary basalt intrusions into mudstone, showing intense 

 crystallization and the formation of sapphire and anorthite 

 felspar from Skye, Scotland. 



2. Judge Docker exhibited enlargements of photographs 

 of trachyte plugs and necks at the Warrumbuugle Moun- 

 tains, taken in 1895. 



3. Mr. G. H. Halligan exhibited views of the Grand 

 Canyon. 



Mr. W. N. Benson described the volcanic geology of Skye 

 basing his remarks on A. Harker's memoir. He illustrated 

 his remarks by maps, photographs and specimens. 



Monthly Meeting, 13 October, 1915. 

 Mr. R. H. Oambage, in the Chair. 

 Thirteen members and three visitors were present. 



