240 ROBERT M. YERKES 



mation concerning all of the birds which are mentioned, but it 

 gives valuable general information concerning a very large num- 

 ber of types of bird, and one may turn to these volumes for 

 general information concerning the natural history of this group 

 of organisms with the certainty of acquiring a large amount of 

 useful information and of being stimulated to further study of 

 the form and behavior of organisms. 



From the point of view of the reviewer, the editors of these 

 volumes richly deserve commendation for their intelligent and 

 thoroughly conscientious rewriting of this portion of the great 

 natural history. It is a work which should be rendered avail- 

 able in several languages. In English, we have nothing at all 

 comparable to it and, as was suggested in our preliminary 

 notice of the new edition, it is very much to be desired that 

 the complete work be rendered into English. 



