Geological Society of London. 287 



upper portion of the series (grits, sandstones, and shales) contains 

 chiefly fossil plants, the most abundant being a Glossopteris. The 

 lower strata (generally argillaceous limestone) contain Producti, 

 Spiriferce, etc., of true Carboniferous type, intermixed with scanty 

 and imperfect remains of the above-mentioned plants. A set of 

 fossils from the head of the Don Kiver were said to agree with those 

 found in the Hunter Eiver series of New South Wales. 



Devonian rocks extend from 18° S. lat. to the southern boundary of 

 Queensland and for 200 miles inland. They consist of slates, sand- 

 stones, and Coral-limestones. The upper portion of this series con- 

 tains an abundance of fossil plants, the deposits containing which, 

 at Mount Wyatt, are interstratified with beds containing Spiriferce, 

 and other fossils of Devonian type occur in beds reached by shafts 

 sunk through these strata. In the limestone of the lower portion 

 of the series seen on the Broken Eiver corals are very numerous. 

 Gold is found in many parts of the Devonian district, and the author 

 entered in considerable detail into its mode of occurrence there. 



Metam Orphic rocks were described by the author as occurring in 

 various localities. At the Cloncurry, Cape Kiver, Grilbert, Peak 

 Downs, Black Snake, Kilkwan, and Goaroomjain Diggings these are 

 mica- and hornblende-schists, whilst at the Ravenswood Diggings 

 the rock is a granite with triclinic felspar. The latter, which 

 contains more or less hornblende, the author regarded as of meta- 

 morphic origin. The author noticed the connexion between the 

 presence of trappean rocks in these metamorphic areas, and in the 

 Devonian area, and the production of auriferous and cupriferous lodes. 



True granites crop out along the eastern coast of Queensland, and 

 these vary much, passing into porphyry and quartz-porphyry, but 

 monoclinic felspar always predominates in them. 



The intrusive Trappean rocks, which are regarded as influencing 

 the production of auriferous veinstones in the Devonian and meta- 

 morphic rocks, are noticed at considerable length by the author, and 

 consist of pyritous porphyrites and porphyries, pyritous diorites and 

 diabases, chrome-iron serpentines and pyritous felsites ; the author 

 considers that this order probably indicates the succession of these 

 rocks in time. The veinstones, he thinks, were probably deposits 

 of mineral matter from the hydrothermal action which preceded, 

 and continued long after the cooling of the traps themselves. 



The volcanic rocks, in the author's opinion, have played a most 

 important part in determining the elevation and present physical out- 

 line of north-eastern Queensland ; they follow the line of greatest 

 elevation on the main watershed at altitudes of from 1500 to 2000 

 feet above the sea-level. The general arrangement of the other 

 rocks referred to is epitomized by the author as follows : — 



"With the exception of the McKinlay ranges, a line drawn 

 parallel with the eastern coast at a distance of 250 miles would in- 

 clude all the Paleozoic, metamorphic, and igneous rocks represented 

 in the colony, both coal-groups lying within the same area. 



" The Mesozoic and Cainozoic systems occupy the surface area to 

 the westward. 



