576 president's address. 



(3) In Queensland the Middle Devonian (Burdekin) formation 

 consists of limestones, conglomerates, white siliceous sandstone, 

 and red and green shales. 



On the track from the Broken River to the Gilbert Diggings, 

 the late Sir Richard, then INlr., R. Daintree, described the type 

 section of the Middle Devonian rocks,* and Mr. R. L. Jackf 

 describes the excellent section observable there in detail. The 

 series commences with 300 feet of basal conglomerate, and com- 

 prises eight beds of coralline limestone having an aggregate 

 thickneSvS of between 2000 and 3000 feet. The total thickness of 

 the strata is estimated at 20,782 feet. As the lower portion of 

 the series, 10,000 feet thick, is not fossiliferous, it may belong to 

 Lower Devonian or even in part to Upper Silurian time. 



Mr. Gibb Maitland, F.G.S., describes^ the strata of Middle 

 Devonian Age on the Upper Burdekin as consisting largely of 

 red shales, and east of the station at the Valley of Lagoons he 

 states that the fine-grained sandstones of this series are crowded 

 with suncracks, and are interstratified with beds resembling fine 

 volcanic ash, testifying of course to contemporaneous volcanic 

 activity. 



East of the Fanning River the Middle Devonian limestone 

 attains the enormous thickness of 7000 feet.§ 



These limestones, composed chiefly of corals (Heliolites, Favo- 

 sites, &c.) and hydrocorallines f Stromatojjora, Stromatopo7^ella, 

 &c.), have all the aspect of ancient coral reefs. The ancient 

 history of this region may therefore be repeating itself to-day in 

 the adjoining areas of the Great Barrier Reef of Australia. 



The oldest land plant yet found in Australasia, Dicranophyllnm 

 australicum, Dawson, was discovered by Mr. R. L. Jack in this 

 Middle Devonian Series, || and has been described by Sir William 



* Q.J.G.S. Vol. xxviii. pp. 290-291. 

 + Geology and Paleeontology of Queensland, pp. 36-38. 

 X Report on the Geology and Mineral Resources of the Upper Burdekin 

 Beds, by A. Gibb Maitland. Brisbane, 1891. 



§ f. R. L. Jack and R. Etheridge, Junr., loc. cit. p. 36. 

 II Loc. cit. pp. 36 and 49. 



