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of Oukaparinga. The rock here is coarser in grain, and on 

 microscopical examination proves to be a uralite diorite. 

 Ilmenitic quartz veins occur, and near the Stirling East 

 schoolhoiise a graphic quartz tourmaline vein. 



Yankalilla. — On the suggestion of Mr. Howchin I made 

 a collection of rocks from the hill on Sections 1186 and 1187 

 of the Himdred of Yankalilla, a mile to the east of Yanka- 

 lilla township. They were epidotized diopside granites and 

 syenit-es, containing sphene and magnetite, probably titanif- 

 erous. It is rather gneissic. Bands of gneissic aplite and 

 granite pegmatite occur, the latter often containing ilmenite. 

 Rather gneissic biotite granite also is present. The whole 

 series intrudes and has strongly silicified a mass of quartz 

 schist. To the east of the intrusion, however, a mica schist 

 occurs rather more like the Houghton-Barossa schist. The 

 extent of this Pre-Cambrian area is not yet proved. To the 

 west it is hidden below Permo-Carboniferous till. To the 

 south-west about five miles it occurs again. Four miles south 

 of Normanville the road to Cape Jervis turns sharply from 

 the coast up a narrow gorge in mica schists and augen 

 gneisses. My attention was first directed to this locality by 

 a specimen presented to the Geological Museum of the Uni- 

 versity by Dr. Woolnough, which was macroscopically iden- 

 tical with the Hoiighton rocks. In the gorge the typical 

 features of the titaniferous magma rocks were fully developed. 

 They intruded the schists, and occurred in abundance in 

 boulders by the roadside and in the creek. Coarse-grained 

 ilmenite in quartz veins, a pegmatite composed of quartz 

 felspar and ilmenite, in roughly equal amounts, hornblende 

 uralite granodiorite diorite, and hornblende diorite, the 

 last a melanocratic rock, Mere observed. As usual, epidote 

 was a common secondary mineral. The gneissic rocks on 

 microscopical examination prove to be closely similar to those 

 of Barossa. 



The stratigraphic relationship of this area was not traced, 

 but it should be remarked that a continuation of these schists 

 along their direction of strike (south-west) for four miles 

 would bring them below Second Valley, where there is a 

 series of phyllites (including a white marble) overlain by a 

 quartzite of great thickness, all dipping easterly. The 

 marble may prove to be the limestone in the River Torrens 

 series ; the other formations would tally well with the lower 

 phyllites and the thick quartzite. Their lithological uncon- 

 formity with gneisses at the gorge is m.ost marked. 



Moonta. — I learn from Mr. Mawson that the country 

 rock of the Wallaroo and Moonta Mines is an actinolite peg- 

 matite, not unlike the yatalite. 



