27 [Vol. xxxvii. 



locality in "vrhicTi an abundance of food shall once more 

 create an excess vitality with the corresponding desire for 

 procreation. 



" So^ too, in some tropical countries elevation is a very 

 potential factor in determining how many eggs shall be laid. 

 Indeed high elevation takes the place of high latitudes, and 

 similarity of climatic conditions produce similar effects. 

 Thus in the higher elevations of the Himalayas we find 

 Thrushes, Flycatchers, Accentors, etc., laying nearly as 

 many eggs as they do in northern Europe, though not 

 nearly as many as they do in the extreme north. On the 

 other hand, in southern India the representatives of these 

 same birds frequently lay only two eggs instead of four or 

 five, as in other parts of the world. 



"Then, too, other factors which are connected with food 

 create temporary and local disturbances which may cause 

 an increase iu the number of eggs laid by one species and 

 yet have the contrary effect in others. Thus in north-west 

 India a plague of locusts will mean that all the Kaptores 

 which prey thei*eon will breed with great freedom, whilst those 

 birds whose food is destroyed by these same locusts will be 

 weak and anaemic, and breed less freely and successfully 

 than in normal years. So, too, an unusual flood will bring 

 water-birds an abundance of food and will entice birds to 

 bi'eed which never normally did so in the district so flooded, 

 whilst those birds which breed in the grass-lands of ordinary 

 years are prevented from breeding at all.'' 



The Rev. F. C. R. Jourdain mentioned that though he 

 had been resident for twenty years in a district where the 

 Common Sandpiper bred freely, and at least eighty nests 

 must have come to his knowledge during that period, not 

 one contained more than four eggs. It was a remarkable 

 fact that in such a limited area in Kashmir, and in such a 

 comparatively short time. Colonel Buchanan should have 

 taken two sets of six and four of five eggs each. 



Mr. Jourdain remarked that while the food supply was 

 apparently the dominant factor governing the number of 

 eggs laid in some cases, other factors, such as the shortness 



