How to Use Keys for Identifying Organisms.

A brief description of the method for using keys of the type included in “Tuatara” is given in this number for the benefit of those who are not familiar with the use of keys as an aid for the quick identification of organisms.

The procedure is as follows:

Commencing at “1”, two alternative and mutually exclusive conditions are listed. When it is definitely decided which condition the specimen being examined fulfils, note the number for that feature as listed at the right side of the key (in the present key, either 2 or 3). Now, on the left side of the key, go to the number selected as above. Under it two further alternative features are listed. Again carefully select the one which applies to the specimen under consideration. This procedure is continued until it leads to a name which will be that of the specimen studied (or of a closely related species) if sufficient care is taken at each stage.

It is very important to avoid all key numbers except those which lead directly from one to the other at each stage.

Editor.