576 F. DEBENHAM. 



3. Dolerite Dyke at mouth of Ettrick River. 



Macroscopic— Ooarse grained dark rock with porphyritic 

 felspars, showing fluxional arrangement. 



Microscopic— Plagioclase, augite (uralite), ilmenite, 

 magnetite, rutile. Tlie structure is granitoid, but there 

 are two generations of felspars. The felspar is much 

 decomposed into saussuritic material. The augite is largely 

 uralitized, and, with the felspar, makes up the bulk of the 

 slide. The ilmenite is much altered to leucoxene. 



In conclusion I wish to express my thanks to all those 

 who have helped me in the work of preparing this paper. 

 Particularly I should like to mention Mr. Reginald Cleveland 

 and Mr. James Bowling, residents of King Island, for help 

 in pointing out interesting localities, and Mr. L. K. Ward, 

 b.a., b.e., for much advice given on the lithological resem- 

 blances to the rocks of Tasmania. My thanks are especially 

 due to Dr. W. G. Woolnough for much advice and assistance 

 in the preparation of this paper. 



