Behaviour of Birds 



by the retreating Germans (British Birds 

 Magazine, vol. xi. p. 67). The sites for nest- 

 ing in the Peronne district were remarkable 

 owing to the absence of buildings. SWAL- 

 LOWS often used the circular Nissen huts put 

 up for the troops, and were extraordinarily 

 tame and confiding. A wooden porch, erected 

 outside a ruined single-room cottage at 

 Roisel, was used directly it was put up. 

 Another pair made valiant efforts to build 

 their nest under the hood of a R.A. battery 

 lorry ; it went out regularly, but the birds 

 carried on. building operations on its return 

 and only gave up after two or three days. 

 A pair of SWALLOWS managed to stick their 

 nest against the vertical wall of a windowless 

 room used as an officers' mess ; the nest had 

 no sort of support underneath (Ibis, 1918, 

 vol. vi. p. 359). In the very heart of a 

 shelled and ruined town SWALLOWS quietly 

 perched on war-telegraph wires, before migra- 

 ting, as though the turmoil of battle were a 

 thousand miles away (Illustrated London News, 

 25.ix.i5). Preparatory to migration the 

 SWALLOWS collected in flocks and might be 



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