they congregate and fly round and round in great circles, at a 

 consdierable height. Small wading-birds, like ringed plovers 

 and dunlin, commonly fly in " bunches." The last named 

 furnish a singularly interesting sight when thus travelling ; 

 for their evolutions are so amazingly timed. As if at a given 

 signal every bird in the troop will change its course at the 

 same moment, and in the same direction, so that, now one 

 sees a fUckering mesh-work of grey, and now a shimmering 

 as of snow-flakes, as first the grey backs, and then the white 

 breasts are turned towards one. But flights such as this 

 are to be seen only during the autumn and winter months. 

 For during the breeding season these little flocks are broken 

 up and distributed far and wide. But there is yet another 

 reason. They wear a totally different dress — ^the courtship 

 or breeding plumage. Herein the upper parts are of a rich 

 chestnut hue, streaked with black, whUe the under parts are 

 black. Even more fascinating to watch are the autumn 

 troops of starUngs on the way to their roosting places. 

 Hundreds at a time, not to say thousands, take part in these 

 flights. Now they rush onward, in one great far-flung sheet, 

 and now they close up into a great, almost ball-hke, mass : 

 and now they thin out till they look like a trail of smoke. 

 But always they wheel and turn and rise and descend, not 

 as separate bodies, but as one. How are such wonderful 

 evolutions timed. The movements of an army on review- 



48 



