READING RIDDLES OF THE ROCKS 113 



surface of the earth ; his great desire is to see 

 as much as possible of what may lie beneath. 

 So the prospector in search of fossils betakes 

 himself to some region where the ceaseless 

 warfare waged by water against the dry land 

 has seamed the face of the earth with count- 

 less gullies and canyons, or carved it into slopes 

 and bluffs in which the edges of the bone- 

 bearing strata are exposed to view, and along 

 these he skirts, ever on the look-out for some 

 projecting bit of bone. The country is an 

 almost shadeless desert, burning hot by day, 

 uncomfortably cool at night. Water is scarce, 

 and when it can be found, often has little to 

 commend it save wetness ; but the collector is 

 buoyed up through all this with the hope that 

 he may discover some creature new to science 

 that shall not only be bigger and uglier and 

 stranger than any heretofore found, but shall 

 be the long-sought form needed for the solu- 

 tion of some difficult problem in the history 

 of the past. 



Now collecting is a lottery, differing from 

 most lotteries, however, in that while some of 

 the returns may be pretty small, there are few 



