548 



though not certainly, newer also than dykes of ophitic 

 dolerite. 1 Lherzolites similar to those here described were 

 found by Dr. Jensen in a monchiquitic lamprophyre dyke 

 in the Nandewar district, which also must be considered 

 post Tri;t->si<\ probably Tertiary in age, a succeeding plm-r 

 to a series of eruptions of alkaline rocks. 2 Rocks like the 

 Dundas inclusions are to be found in the neck at Norton's 

 Basin on the Nepean River, and I have seen a micro slide 

 of a dolerite inclusion labelled "Rooty Hill," probably from 

 the dyke there. Gabbro boulders occur in the basalt of 

 Glen Alice (Oapertee) and colourless pyroxene crystals 

 (xenocrysts) in the basalts of Mount Wilson, Rooty Hill, 

 Thirlmere and Long Bay. Pyroxene containing picotite 

 occurs in the nepheline basalt of Burragorang and aggre- 

 gates of olivine, hornblende and picotite in the Bulli basalt 

 dyke." Augite, picrite and eclogite occur in the breccia- 

 filled pipe at Bingera, and are correlated by Mr. Card with 

 above mentioned occurrences. 4 Numerous instances of 

 eclogite occurring in breccia pipes in Southern Monaro are 

 cited by Mr. Pittman. 5 Mr. E. O. Andrews compares the 

 "pebbles" of the Eleanora dyke at Hillgrove, with the 

 inclusions of Dundas, noting the difference in the containing 

 rock. 



Through the kindness of Mr. Card, I was enabled to 

 obtain micro slides of an inclusion and its host. The con- 

 taining rock is a lamprophyre rather than a basic granite. 

 It is camptonitic in character, composed of long brown 

 hornblende prisms and smaller brown hornblende crystals, 

 together with a few larger phenocrysts of nearly colourless 



1 J. li. Jaquet and G. W. Card, Rec. Geol. Sur. N.S.W., 



' Proc. Linn. Soc. N.S.W., 1907, p. 884. 



3 Rec. Geol. Sur. N.S.W., Vol. Til, pt. iv. * hoc. cit., p 



5 Ann. Rep. Department of Mines, N.S.W., 1908. 



° Report on the Hillgrove Goldfield, Department of I 

 ■Mineral Resources No. 8, 1900, p. 25. 



