’Geology.] 
NATURAr. HISTORY. 
6fj9 
jasper; and above it was a mass of sand- stone, more than 
sixty feet thick. — -(Narrative, vol. ii. p. 26.) 
Sunday Island, near Cape Grenville, about one hundred 
and seventy miles west of north from Cape Melville.— • Com- 
pact felspar^ of a flesh-red colour; very nearly resembling 
that of the Percy Islands, above-mentioned. 
Good’s Island, one of the Prince of Wales’s group, about 
latitude 10°, thirty-four miles north-west of Cape York. — 
The specimens, in Mr. Brown’s collection from this place, 
consist of coarse-slaty porpJiyritic conglo7nerate^ with a base 
of greenish-grey compact felspar, containing crystals of red- 
dish felspar and quartz. This rock has some resemblance to 
that of Clack Island above-mentioned. 
Sweer’s Island, south of Wellesley’s group, at the bottom 
of the Gulf of Carpentaria. — A stalactitic concretion of 
quartzose sand, and fine gravel, cemented by reddish carbo- 
nate of lime; apparently of the same nature with the stem- 
like concretions of King George’s Sound : (See hereafter, 
p. 621.) In this specimen the tubular cavity of the sta- 
lactite is still open. 
The shore, in various parts of this islan^, was found to 
consist of red ferruginous matter, (^Bog -iron-ore?) sometimes 
unmixed, but not unfrequently mingled with a sandy cal- 
careous stone ; and in some places rounded portions of the 
ferruginous matter were enveloped in a calcareous cement. 
BentiJick Island, near Sweer’s Island. — A granular com- 
pound, like sand-stone recomposed from the debris of 
granite. Brown hematite-, enclosing quartzose sand. 
PisoNiA Island, on the east of Mornington’s Island, is 
composed of calcareous breccia and pudding- stone ^ which 
VoL. IL 2 R 
