BY W. N. BENSON. 533 



cline, and also quartz in irregular grains. There is a little 

 granophyric and pseudospherulitic intergrowth of quartz with 

 orthoclase. Very subordinate biotite occurs, and some apatite. 



Age of the Granites. — From the evidence obtainable in the 

 district here described, we cannot fix the age of the granites 

 more definitely than post-Silurian. From their examination of 

 the whole Bathurst district, both Ross and Curran believe that 

 it is probable that the granites are the result of two intrusions, 

 the first pre-Devonian, the second post-Devonian. 



iv.— Chlorite Schist. 



The chlorite schist occurs, as before noted, in a wide band, 

 one-quarter of a mile west of the Newbridge Railway Station. 

 It runs in a northerly direction, crossing the present railway 

 cutting, appearing again in the old railway cutting; and frag- 

 ments of the schist are enclosed in a quartz vein about half a 

 mile west of the slate quarry on Reedy Creek. It is so soft that 

 it does not form an outcrop, and so can be examined in the 

 railway cutting only. 



Macroscopical. — Green and yellow striped, fibrous, splintery, 

 highly cleaved in three directions, falling into acute rhombohedra, 

 translucent and wax-like to the touch. 



Microscopical. — Composed of talc in white, strongly birefringent 

 fibres, running through and occasionally forming ^ubradiating 

 bunches in a predominant ground-mass of green pleochroic 

 chlorite of very low, double refraction 



With a magnification of 400 diameters numerous aggregates of 

 brown rutile needles are to be seen, and also some zircons. 



Until a more extensive examination has been made in the 

 field and laboratory, I can off'er no explanation of the origin of 

 this peculiar rock. 



V. — Slates. 



The slates of this district lie in a wide band, running in a S.W. 

 direction across Galbraith Parish, between the andesites and 

 granites, by the latter of which they have been intruded. Thoy 

 are the oldest rocks exposed in the district. In age they are 



