126 Proceedings of the Royal Society of Victoria. 



an admirable illustration of the contorted character of the gneiss 

 and schist of Commissioner's Creek. 



My first excursion from Yackandandah was along Commis- 

 sioner's (Jreek in order to get a general idea of the creek and the 

 rocks on both sides. The schists are exposed in the first cutting 

 on the road along Commissioner's Creek. They strike to the 

 north, and stand nearly vertical. They are traversed by euritic 

 dykes, of which the largest is two feet in width. The next road 

 cutting shows weathered mica schists, with small quartz veins. 

 After crossing a small brook, and just before reaching another 

 road cutting, a track leads to the left, by a watercourse passing 

 near an old roofless wooden house. The tx'ack leads to a quarry, 

 at the foot of the steep ridge. The rocks here are as metamorphic 

 as those on the eastern side of the valley. The strike is from 

 N.N.W. to S.S.E., and the main rock is a fine grained black 

 gneiss, cut through by some dykes. Search for the junction with 

 the ordovician series had, therefore, to be made further to the 

 south-west. The ridge which is marked on the map as rising to 

 867 feet, is composed mainly of a medium grained gneiss and 

 dykes of red pegmatite. On the ridge is some coarser hornblendic 

 gneiss, the strike of which is generally to the north-west parallel 

 to Commissioner's Creek. On the south-western side of this 

 ridge lies Wood Cutter's or Sawpit Gully, the rocks on the left 

 bank of which are mainly schists and gneiss. At the junction of 

 Wood Cutter's or Sawpit Gully and Twist Creek there are some 

 excellent exposures on the bed of the valley, where the gravel has 

 been sluiced away during some mining operations. On the bed 

 of the stream and on the right bank are some good exposures of 

 contorted gneiss and schists, striking north-west by north. A 

 very coarse-grained pegmatite cuts through this series. A little 

 way up Twist Creek from the junction of Sawpit Gully are some 

 beds of slate and sandstone, with a strike of from N.N.W. to 

 N.N.W. by N., and dipping 80 degs. to the west. In the best 

 exposure the beds are vertical, and the strike is N.N.W. | N. In 

 the angle between Sawpit Gully and Twist Creek is a wooded 

 spur, from which the only specimens obtained were faulted 

 quartzite and iron-stained micaceous slate. Ascending Twist 

 Creek a series of green sandstones with quartz veins, slates, 

 quartzites, and chloritic slates are seen on the bed of the stream. 



