308 BRITISH BIRDS. 



soil — sand, with many flints strewn on the surface. With 

 this, and the browns and greys of mosses and lichens, the 

 plumage — whether down or feather — assimilates to a 

 remarkable degree. While it keeps to the special environ- 

 ment the crouching habit is of undoubted value, but on 

 ground of a different nature, with which the colour of the 

 down would not harmonise so well, one can imagine the 

 crouching habit becoming a constant menace to the 

 existence of the species, as it would, under such changed 

 conditions, become a conspicuous and easy prey. 



Two of the photographs. Figs. 3 and 4, well illustrate 

 this point. The two birds depicted were nest-mates, and 

 the first one. Fig. 3, was photographed just as it was 

 fomid, the photograph giving an unexaggerated im- 

 pression of the bird and its environment, which is typical of 

 the district. The second young bird was found crouching 

 not far away and (quite experimentally) was made to realize 

 that it was discovered. It ran thirty or forty yards 

 before it crouched again, and, owing to a slight rise in the 

 ground, I failed to note the exact spot where it ceased 

 running, and for some time I searched in vain. At last 

 from a distance of four or five yards, I detected it near some 

 nettles, crouching on a dark patch of soil and dead nettle 

 leaves and stems, where it was ridiculously conspicuous. 

 Realizing that it would make an interesting comparison 

 with the other I fetched the camera and photographed it 

 as quickly as I could, not that there was any real fear of 

 the little bird moving, for it apj)eared"to be as thoroughly 

 convinced that it was invisible, as when it was on the 

 usual flint-strewn sandy soil. 



