64 



THE AMEBIC AX NATURALIST 



[Vol. L 



vastly increased by the deduction of formulae suitable for dealing 

 with data of the most diverse sorts. 



The most valuable feature of a summary such as the present 

 may possibly not lie in the fact that it exhibits to biologists the 

 wide array of statistical tools which are now available for dealing 

 with the most diverse sorts of data which they may collect, and 

 shows where directions for their use may be found, but in the 

 suggested warning that the hasty application of the first learned 

 or the most easily calculated formula may lead to constants of 

 little value. Most biologists can use a scalpel or a beaker with 

 great success, but many at least would hesitate to try to handle 

 without special training all the instruments which are to be seen 

 in the surgeon's case or to use all the glassware on the organic 

 chemist's shelves. Each kind of tools require their special train- 

 in--. Notwithstanding popular conceptions to the contrary, this 

 is also true of the biometric tools. 



J. Arthuk Harris 



