52 THE NOTEBOOK OF A CITY NATURALIST, 



coming towards me, it pitched on some rougk broken 

 ground, and I noticed t>vG of the birds had a different gait, 

 and were slightly larger than the others.. On moving, there 

 was a difference in their flight, and when they turned from me 

 I recognised their eonspicuoRS markings — the bright white 

 flash which is enough to attract attention at any distance, 

 for the wheat-ea^r is one of our most noticeable wild birds. 

 This flash light must be looked upon as an absolute failure 

 in protective colouring, and cannot subserve the same pur- 

 pose that has been suggested as an excuse for the white 

 underside of the rabbit's taiL 



Having taken this stroll, may I ask you to observe a few 

 points ? The sand-martins nesting out of their usual site, a 

 sand-bank, in holes in walls — their food supply remains, — 

 many other birds are extinct, their nesting places and food 

 supplies being immediately connected. 



Why does the sand-martin drill holes in banks for the 

 fulfilment of its maternal instinct ? Its bill is weak, its 

 feet diminutive, its body weight almost nil, and its tail 

 ■cannot be used as a fulcrum from which to give powerful 

 blows v/ith a weak tool. 



Why does the house-martin use its delicate beak as a hod 

 and trowel ? The bill is not what we should design for the 

 purpose. 



Why does the swallow make an open nest ? Not to 

 accomraodate its tail, as has been suggested. These birds 

 with similar habits, and we might add the case of the swift, 

 nest differently and all apparently under inappropriate 

 conditions. 



Watch the young birds ; we talk of their learning to fly — 

 the bird is pushed out, or falls, or boldly hops on to the edge 

 of its nest, in hedgerow or ditch, and scrambles or hops or 

 fluttera on to a twig, it gets up higher and falls, then it 



