CHALK MAKERS, OR FORAMINIFERA. 59 



a garden snail, and placed in a line, that line of shells 

 would be 3,072 miles in length, and would occupy an 

 express train seventy-seven hours to go from one 



FIG. 12. CHALK OF DENMARK. 



end to the other, at the continuous rate of forty miles 

 an hour. 



It would be folly to attempt any calculation of the 

 myriads of these little shells which are buried in 

 the chalk of England alone, without any reference to 

 similar beds in continental Europe (fig. 12). The 



