48 THE VICTORIAN NATURALIST. 



origin. Fresh additions come from the seaward, and close to 

 the coast bare drifting sand dunes are common, while, as we pass 

 inland, vegetation makes its appearance, and we may get the 

 dense scrub-land of the Nepean Peninsula, or the well-grassed, 

 park-like country of Cape Otway or Warrnambool. The boundary 

 of the loose dunes is ever shifting ; now they are marching inland, 

 overwhelming roads, fences, and paddocks, as on the coast line 

 near Barwon Heads, where the old road for miles is destroyed, 

 and is now scarcely traversable even on foot, though thirty years 

 ago it was, I believe, a beautiful grassy track. In other places 

 again the line of vegetation has crept seaward to the very cliffs, 

 and the shifting sandy billows have been frozen as by a magic 

 touch. The struggle between shifting sand and plant life is a 

 keen one, and the victory now lies with the one and now with 

 the other ; a too rapid advance is here repulsed, and here again 

 there is a steady forward march. 



It is with certain phenomena of this shifting border line that I 

 wish to deal at present. Occasionally when the drifting sand is 

 blowing away there are exposed to view thickets of what, at first 

 sight, appear to be petrified stems and roots of shrubs. The 

 nature of these curious bodies has long ago been worked out, for 

 they are not confined to Australian shores, but are found in other 

 parts of the world ; but popular misconception as to their nature 

 makes it appear advisable to give some account of them. 



In one of his presidential addresses Prof. Ralph Tate tells us 

 that the first recorded geological observation for Australia relates 

 to these pseudo-fossils, for in 1791 Vancouver, who discovered 

 King George's Sound, says that Bald Head was covered with a 

 coral structure, by which he meant the objects in question. 

 Flinders thought they were petrified trees when he saw them 

 about ten years afterwards. In 1836 Charles Darwin visited 

 Bald Head in company with Captain FitzRoy, and his explana- 

 tion, though not the correct one, is a closer approach to 

 the truth than that of the two previous observers. He says 

 in his " Journal of Researches " : — " According to our 

 view, the beds have been formed by the wind having heaped 

 up fine sand, composed of minute rounded particles of 

 shells and corals, during which process branches and roots of 

 trees, together with many land shells became enclosed. The 

 whole then became consolidated by the percolation of cal- 

 careous matter, and the cylindrical cavities left by the decaying 

 of the wood were also filled up with a hard pseudo-stalactitical 

 stone. The weather is now wearing away the softer parts, and in 

 consequence the hard casts of the roots and branches of the 

 trees project above the surface, and, in a singularly deceptive 

 manner, resemble the stumps of a decayed thicket." 



Jukes, in his " Sketch of the Physical Structure of Australia," 



