HO W EXTINC T MONS TERS A RE PRESER VED. 2 3 



to future explorers. Already, one remarkable snd lar^e horned 

 quadruped has come from this region ; and it is known that other 

 valuable treasures are sealed up within these hills, only awaiting 

 the "open sesame" of some enterprising explorer to bring them 

 to light. 



As previously pointed out, deposits formed in lakes are the 

 most promising field for geologists in search of the remains of 

 old terrestrial quadrupeds and reptiles ; but, unfortunately, such 

 deposits are rare. 



It is very much to be regretted that the carelessness and in- 

 difference of ignorant workmen in quarries, clay-pits, and railway 

 cuttings have sometimes been the cause of valuable fossils being 

 broken up, and so lost for ever. Unless they are accustomed to 

 the visits of fossil-collectors who will pay them liberally for their 

 finds, the men will not take the trouble to preserve any bones 

 they may come across in the course of their work. (An example 

 of this negligence will be found on p. 95.) But when once they 

 realise that such finds have what political economists call an 

 '' exchange value," or, in other words, can be turned into money, 

 it is astonishing what zealous guardians of Nature's treasures they 

 become ! For this reason collectors often find what Professor 

 Bonney calls the " silver hammer " in other words, cash more 

 effective than the iron implement they carry with them. 



