vi PREFACE 



of the climatology of deserts, and of the life-history 

 of the great majority of the smaller animals, and 

 there is at present a complete absence of experi- 

 mental work upon them. It is partly in order to 

 summarize our present knowledge and to draw 

 attention to the graver deficiencies in it that this 

 book has been written. 



The study of the desert creatures and their 

 environment leads one to a very fascinating meet- 

 ing-place of several sciences. It can only be 

 approached with the help of botanists, meteorol- 

 ogists, physicists, and others. My debt to my 

 fellow-workers is the greater because the book was 

 written in Jerusalem, without access to a good 

 library ; I have therefore been forced to rely on the 

 kindness and generosity of correspondents, many 

 of them unknown to me personally. In many cases 

 I have embodied the information which they have 

 given me, and made no acknowledgment of it in 

 the text, because my purpose has been to eliminate 

 foot-notes and bibliography from a book which can 

 make no claim to completeness. 



My friends Mr. C. B. Williams and Mr. V. H. W. 

 Dowson have allowed me to draw upon them for 

 several illustrations. Fig. 11 is from a photograph 

 taken by Mr. F. W. Green, and to him and to the 

 Director of the Geological Survey of Egypt I wish 

 to express my gratitude. For Fig. 32 we are in- 

 debted to Dr. R. I. Pocock and the Zoological Society 

 of London ; for Fig. 34 to Mr. E. C. Stuart Baker 

 and the Bombay Natural History Society ; for Figs. 

 38 and 41 to Dr. J. Grinnell and the Museum of 



