114 



spreads over the shell limestone and the shell sand, and has 

 enclosed the shells o£ the latter. 



As elsewhere m the colony, these recent marine-beds contain 

 the usual assemblage of shallow water forms of the present 

 coast line, but in addition are characterised by the abundance 

 of individuals of a few species either very rare or extinct in 

 our waters. In the Talata deposits, the most notable are 

 Area trapezia, Cryptodon ovulum, Dentalium Tasmatiensis, and 

 Columbella australls. The sand drift inside the dunes of the 

 " Roe Plains " at Eucla rests on a calciferous sandstone, con- 

 taining the common shells of the present coast. The shells of 

 the Mactrae and other bivalves, being in apposition, prove that 

 the fossils lived and died on the spots where now found. The 

 highest elevation at which these evidences of recent oscillation 

 of level were seen is at about twelve feet above high water. 



As previously stated (p. 104), the Bunda cliffs are at their 

 extremities fronted by an undercliff of consolidated blown 

 sands, which belong to the series of seolian deposits just 

 described. Plate iv., fig. 2 exhibits the manner in which they 

 have been accumulated in front of the sea wall, have acquired 

 some debris from the cliffs, and have streamed over upon the 

 crown of the escarpment ; the truncated seaward face of the 

 undercliff is characteristic not only here, but of other parts of 

 the coast line. That the sands, which form the knolls on the 

 seaward edge of the Bunda Plateau referred to at p. 99 have 

 been blown up from the shore is indicated by their mode of 

 occurrence, and by the nature of the material, which I find to 

 consist of rounded grains of limestone dissolving freely in acid 

 and leaving an aluminous and sandy residue of about 7'6 per 

 cent. 



The sands which cover the Bunda cliffs are more often con- 

 solidated, especially in the lower portions ; and alternations of 

 sand, sandroek, and travertine generally prevail in all the 

 sections. Not unfrequently the loose sand beds are penetrated 

 by stalactitic masses of consolidated sand, and have in them 

 erect stole-like masses of the same material in various shapei 

 and sizes, the latter ranging up to one foot in diameter and up 

 to a height of two and a half feet. They must have originated 

 from the precipitation of carbonate of lime around roots, 

 branches, and stems of shrubs, whilst they possessed consistency ; 

 and the cavity which was formed by the subsequent decomposi- 

 tion of the vegetable matter was filled by the same process. 

 Similar concretionary bodies have been described by Flinders, 

 as entombed in the calciferous sands of Bald Head, King 

 George's Sound ; but he mistook them for corals, whilst the 

 true explanation of their origin was left to Charles Darwin 

 (vide- Journal of Naturalist, 12 ed.. p. 450). And their 



