NOTICES OF NEW BOOKS. 437 



language he only learned three phrases, "but the use of a hiding 

 contrivance greatly enlarges one's appreciation of bird-language, 

 a rich field awaiting investigation by ornithologists." This is 

 really encouraging and advanced reading, and one of the very 

 few recognitions of the vast revolution in evolutionary and 

 zoological conceptions which will ensue when the language of 

 other animals than ourselves has been studied and understood; 

 this has now ceased to be regarded as quixotic, though too 

 frequently relegated to the region of the unlikely. That pro- 

 fessional egg-collectors are an absolute danger to the survival of 

 many rare birds is apparent by the wise withholding of the 

 locality where Dr. Heatherley and his friends made their impor- 

 tant observations on living Peregrine Falcons. 



The numerous illustrations show what photography is doing 

 for ornithology, and the method will undoubtedly be applied to 

 other animals by other students and lovers of Nature. In his 

 introduction we are glad indeed to read that " The full notes 

 will, I hope, appear later in the ' Zoologist.' " 



Evolution by Co-operation ; a Study in Bio- economics. By 

 Hermann Ebinheimer. Kegan Paul, Trench, Triibner 

 & Co., Ltd. 



This book is largely a disputation. It is strongly anti- 

 Darwinian, especially so far as Natural Selection is discussed, 

 but it leaves the problem very much where the author found it. 

 The recognition of Darwin's theory of Natural Selection as a 

 great but not sole factor in evolution is one thing, the acceptance 

 of the "all-sufficiency " of Natural Selection in our conceptions 

 of evolution is another. Many naturalists hold fast to the first 

 without subscribing to the second and more recent formula. 

 There is great truth in the prophecy of Huxley— quofced by Mr. 

 Pteinheimer — that " The new generation educated under the 

 influences of the present day will be in danger of accepting the 

 main doctrines of the ' Origin of Species ' with as little reflection, 

 and it may be with as little justification, as so many of our 

 contemporaries rejected them." In fact, this has come to pass. 

 But the method of Darwin was built on observation and reflection, 

 rhetoric is absent in his deductions, and he who would be a 



