220 PROCEEDINGS OF THE MALACOLOGICAL SOCIEIT. 



In the following year Mr. J. B. Jaqnet ' offeretl a fuller account of 

 the deposits at White Cliffs, and similaily regarded thera as Upper 

 Cretaceous and contemporaneous with the Desert Sandstone of 

 Qu«'enslaiid (an extensive formation originally described by Daiiitree,^ 

 who, in the absence of accurate fos.siliferous evidence, wrongly 

 considered it as part of the Kainozoic system). The opal beds were 

 referred to as resting on Palaeozoic rocks, and consisting of con- 

 glomerates and kaolin, the fossils found in them being mentioned as 

 Mollusca, Belemnites, and wood. Scattered throughout the deposits 

 were "enormous waterworn boulders " of a vitreous-looking sandstone 

 which, when broken open, exhibited thin veins of opal as well as 

 " impressions of characteristic Devonian Mollusca and other inverte- 

 brates ". These boulders were stated to have been derived from 

 Palaeozoic conglomerates and sandstones occurring to the westward of 

 the opal-field It was further mentioned that "the occurrence of 

 nodules and veins of opal, the re])lacem(Mit of the remains of Mollusca 

 and other org.inisms by opal, and the deposition of opaline quartz in 

 the interstices of the conjilomerate belonging to this formation, and 

 the foreign boulders of sandstone which are found in it, would seem 

 to indicate that at some period the beds had siliceous waters running 

 through them The presence of hydrous silica in various forms seems 

 characteristic of these beds wherever they have been observed ". 



Mr. F. G. de V. Gipps ' in 1894 referred briefly to some 

 opalized organisms he had found at White Cliffs, which included 

 Plesiosaurian bones, crinoid arms, and wood ; and the following 

 Mollusca determined by Mr. Etheridge, jun. : Maccoyella reflecta, 

 Tellina sp. indet., Modiola, Natica variahilu, and Belenmites canhami. 



During 1895 Dr. Henry Woodward* exhibited at the Geological 

 Society some "opalized Cretaceous fossils, consisting of a tooth of 

 Polyptychodon [now in the Geological Department of the British 

 Museum, R. 2614], the guard of a Belemnitella, and a bivalve shell, 

 from New South Wales", and "precious o])al having the form of 

 a Natica'''' \ they presumably came from White Cliffs, although no 

 particular locality Avas stated in this bi'ief announcement (see 

 11. Etheridge, jun., Mem. Geol. Surv. N.S.W., Palaeontology, No. xi, 

 p. 6, 1902). 



Interesting observations on the opalization of fossil organic remains 

 from White Cliffs were published by Mr. Etheridge, jun.,^ in 1897, 

 when describing some reptilian remains [Cimoliosaurus) from that 

 locality. He refeiTed to the occurrence in those beds of " Crinoid 

 remains, the shells of Pelecypoda and Gastropoda, portions of 

 Belemnite guards, Sauropterygian bones, and an Ammonite wholly 



1 " On the White Cliffs Opal-field" : Ann. Rep. Dept. Mines Agric. N.S.W. 



for 1892-3, pp. 140-2. 

 ^ "Notes on the Geology of Queensland": Quart. Journ. Geol. Soc, 



vol. ssviii, p. 275. 1872. 

 * Trans. Australasian Inst. Min. Eng., vol. ii, pp. 70-80, 1894. 

 ■• Quart. Journ. Geol. Soc, vol. li, Proc, p. iii, 1895. 

 ^ " An Australian Sauropterygian {CAmoUosaurus) converted into Precious 



Opal " : Eec. Australian Mus., vol. iii, No. 2, pp. 19-27, pis. v-vii, 1897. 



