40 RELICS FROM THE WRECK 



crocodile? Secure within the panoply of his strong ar- 

 mour, where was the enemy that would dare encounter this 

 leviathan of the Pampas ? or in what more powerful crea- 

 ture can we find the cause that has effected the extirpation 

 of his race ? His entire frame was an apparatus of colossal 

 mechanism, adapted exactly to the work it had to do. 

 Strong and ponderous in proportion as this work was heavy 

 and calculated to he the vehicle of life and enjoyment to a 

 gigantic race of quadrupeds, which, though they have ceased 

 to be counted among the living inhabitants of our planet, 

 have in their fossil bones left behind them imperishable 

 monuments of the consummate skill with which they were 

 constructed." 



The oolite quarries of Portland have been long remark- 

 able for their containing certain strata called the " dirt- 

 beds/ 7 in which the stems and branches of coniferous trees 

 and cycadesa* are found in considerable abundance. Many 

 of the trees as well as the plants are still erect (see Fig 8.), 

 with their roots ramified in the dirt-beds, which appears to 

 be the soil in which they grew. " On my visit/' says Dr. 

 Mantell, " to the island in the summer of 1832, the surface 

 of a large area of the dirt-bed was cleared, preparatory to 

 its removal, an.d a most striking phenomenon was presented 

 to my view. The floor of the quarry was literally strewed 

 with fossil wood, and I saw before me a petrified tropical 

 forest ; the trees and plants like the inhabitants of the Alg, 

 in the Arabian story, being converted into stone, yet still 

 maintaining their place, which they occupied when alive! 

 Some of the trunks were surrounded by a conical mound of 

 calcareous matter, which had evidently once been earth, and 

 had accumulated around the base and roots of the trees. 

 The stems were generally three or four feet high, their 

 summits being jagged and splintered, as if they had been 



* A genus of plants allied to the palms and ferns. 



