642 (yol. R. Meinertzhagen on Birds from [Ibis, 



Average -per cent. Mean 



humidity. rainfall in 



inches. 



Race. Soil. Locality. Tear. April ^- Tear. April Sf 



Nigricans Black alluvial ... Central Egyptian 70 



Delta. 



Maculnta Dark alluvial, with Cairo 68 



a percentage of Helouan 62 



sand. 



Meridionalis. . Dark brown, often Crete 67 



red. 



Dark brown Cyprus 77 



Cinnamomiria Reddish Beirut 68 



Brown Haifa 70 



Zion Brown to pale Damascus 78 



brown. Tiberias 62 



Jerusalem 65 



Brachyura . . . Pale brown and Suez 55 



sand. Gaza 72 



ElArish 76 



Port Said 74 



Solium 76 



From the above lable, I conclude that Crested Larks are 

 influenced in tlie colour of their plumage by protective 

 resemblance to the soil on w hicli tliey live, and that neither 

 humidity nor rainfall has any effect on their plumage. 

 This same influence apjiears to affect nearly all ground-birds 

 which more or less live in the open, such nn j\t)imomanes, 

 Alcemon, OUnaidJie desert i, hyremopldla., Alectoris, Pterocles, 

 etc. 



Finally, I would point out that three races of the (Jrested 

 Lark (^idyrlcans, macidata, and brachyura) have been living 

 in confinement in the Giza Zoological Gardens near Cairo 

 (whei'e the local wild race is macidata) for many years, and 

 have been subjected to identical conditions. These birds 

 have moulted regularly true to their respective races, and 

 have shown no inclination to change the colour of their 

 plumage. 



I do not ])retend in the above note to have suggested 

 anything new, but when this theory is worked out in detail, 

 it may help those of us who interest themselves in the 

 subject of the effect of external conditions on the problems 

 of evolution. 



