THIS paper consists of notes on the Geology of Mount Morgan district supplementing the work of Messrs. Newman and Brown, published by the Institute, together with a preliminary geological map of some 25 sq. miles of the district around Mount Morgan. An old map of the district with scanty and partly inaccurate information was taken as a foundation for this one. The writer's bearings were measured with a Brunton's pocket transit and the distances by pacing, so the boundaries of the different formations are only approximate between the points accurately mapped on the plan. Furthermore, the rough nature of the country-some of the hills are almost inaccessible- introduced a difficulty in reading the geological history of the locality from the information shown on the map. With this caution against taking the map as absolutely accurate, the following considerations are submitted:- Mount Morgan is situated on an elevated plateau from 700 to 1400 ft. above sea level, the original mountain top having an elevation of 1247 ft. above sea level, and the Mount Morgan railway station 744 ft. An abrupt fall to the surrounding plains takes place on the north, east and south sides, at a distance of 3 to 5 miles from Mount Morgan. The writer has not fully explored the western side, but he understands it is fairly ragged for several miles.