1 48 Geological Society. 



of a mountainous region, a reddish granite occurred, and the prevail- 

 ing formation in the hilly district itself was a gray granite. Leaving 

 this mountainous country and directing his course south-westward, 

 Mr. Cunningham entered upon a less elevated region, composed of 

 clay slate ; and in lat. 29° he arrived at a deep gorge similarly con- 

 stituted, and traversed by a rapid stream, in the bed of which he 

 noticed large boulders of the gray granite. During the next 4-0 

 miles the only rocks noticed were reddish granite and fragments of 

 basalt. In lat. 29° 26' large masses of a fine quartzose conglomerate 

 occurred, and they were afterwards found to be very generally scat- 

 tered over the adjacent country. The boundary hills of Wilmott 

 Valley are stated to be a fine-grained gray granite ; and those which 

 form the head of it, in lat. 30° 11', of brownish porphyry, containing 

 grains of quartz. The party having crossed these hills subsequently 

 traversed Liverpool Plains and the Dividing Range to Hunter's 

 River, and then returned to the station from which they originally 

 set out. 



Mr. Cunningham next offers some remarks on the geology of 

 Moreton Bay and Brisbane River, both of which he visited in 1828 

 for the purpose of connecting his observations at the foot of the 

 Dividing Range in lat. 28° with the sea coast. 



The western shores of Moreton Bay, from the entrance of Pumice- 

 stone River to Red Cliff Point, are faced by a reef of considerable 

 breadth, which at low water is stated to exhibit a ledge of chalcedony. 



In tracing the Brisbane River, which falls into Moreton Bay, the 

 first rock observed was talc slate or chlorite; and opposite the settle- 

 ment, 16 miles from the mouth of the river, is a quarry of pinkish clay- 

 stone porphyry, used for building. In the ravines further up occurs 

 serpentine traversed by veins of asbestos and magnetic iron. Sixty 

 miles from Moreton Bay, ledges of hornstone crop out in the banks; 

 and in the same part of the river a considerable seam of coal appears 

 in its channel. A portion of the stern of a fossil plant, presenting 

 *' concentric fibrous bands, and a longitudinal foliated structure at 

 right angles to the bands," was found in the vicinity of the seam of 

 coal. At " the limestone station" on Brenner River, which falls into 

 the Brisbane, Mr. Cunningham procured a series of specimens, 

 which consisted of yellowish hornstone, indurated white marl, re- 

 sembling some of the harder varieties of chalk, and containing im- 

 mense masses of black flint, bluish gray chalcedony passing into 

 chert, and a gritty yellowish limestone. A bed of coal has likewise 

 been noticed in the Brenner, and traced from it to the Brisbane. 

 To the south of the limestone station is a remarkable hill, consist- 

 ing of trap, called Mount Forbes; and 50 miles to the south ot 

 the penal settlement on the Brisbane is the Birman range, from 

 which the author procured specimens of compact quartz rock; and 

 from Mount Lindsay, likewise south of the 13risbane, he obtained 

 specimens of granite. 



In addition to the collection from the districts already alluded to, 

 Mr. Cunningham has added another, made by Capt. Sturt in an 

 excursion from Bathurst to the marshes of the Macquarie,and hence 

 to the Darling River. It consists of carbonate of copper from a 



