just as the platysoma of the Old Red Sand- 

 stone vanished in the Magnesian Limestone ; 

 or else becoming dwarfingly modified previous 

 to extinction : similarly to the diminution of 

 the seventy foot iguanodon into the four foot 

 and perishing iguana which has outlived the 

 age and environment -which called its giant 

 ancestor into being. 



In this ever recurring disappearance, or 

 modification, of animal and vegetable forms 

 there is nothing strange. Everywhere about 

 us we see waged the pitiless battle for life 

 of which it is the inevitable outcome. Just 

 as the dandelion, the plantain and the bur- 

 dock extend their broad leaves o'er the verd- 

 ure of the meadow, starving and exhaust- 

 ing the grasses around them; just as the 

 weeds of the garden o'erwhelm with rank 

 luxuriance the feebler cultivated vegetables 

 during a brief period of neglect ; and just 

 as species of birds and animals become ex 

 tinct from their merciless slaughter by bar- 

 barous man who spares not his own weak 

 er kind, varieties of his race thus fading 

 from sight ; so there is a continual process 

 of elimination and substitation going on in 

 the great laboratories of Nature ; the use- 



