130 C. A. SUSSMILCH. 
NOTE on THE SILURIAN ano DEVONIAN ROCKS 
OCCURRING TO THE WEST oF THE CANOBLAS 
MOUNTAINS NEAR ORANGH, N.S.W. 
By ©. A. SUSSMILCH, F.G.S. 
[With Plates XIV. - XX.] 
[Read before the Royal Society of N.S. Wales, November 7, 1906.] 
I. GENERAL PHYSICAL FEATURES. 
THE area referred to in this note occurs immediately to 
the west of the Canoblas Mountains, about fourteen miles 
from the town of Orange. It comprises the central and 
southern portions of the parish of Barton, county of Ash- 
burnham, together with a small portion of the adjoining 
parish of Bowan. The most prominent physical feature, 
particularly when viewed from the west, is a barren rugged 
ridge of Devonian rocks, trending nearly north and south, 
and having an elevation of about 3,100 feet above sea level. 
It is known locally as the Black Range. To the east are 
the lower spurs of the Canoblas, which, five miles away, 
culminate in the Old Man Canoblas 4,610 feet in altitude. 
Although so much lower than the Canoblas, the Black 
Range is a much older feature; it is probably portion of 
the peneplain described by Mr. C. HE. Andrews.’ called by 
him the Lithgow Plain. The Canoblas have resulted from 
the building up of volcanic material upon the partly dis- 
sected Lithgow Plain. The main drainage system is Oaky 
or Bourimbla Creek; this and its tributaries Spring, Gap, 
and Quarry Crece:* have cut their channels across the Black 
Range, thereby exposing good sections of the Silurian and 
Devonian strata. 
? Proc. Linn. Soc. N.S.W., Vol. xxvut., p. 786. 
