250 FRIENDS WORTH KNOWING. 



ing chirrup being all its voice can accomplish; nor is it a 

 handsome bird — simply sooty-brown above, white beneath, 

 with a brown breast. To its grace of motion and charm- 

 ing home-life we attribute that in it which attracts us. 



Although probably the least numerous of all the sw\al- 

 lows, they do not seem so, because of the great compa- 

 nies which are to be seen together wherever they are to be 

 found at all ; and because, leading a more sequestered life, 

 they are not usually brought into direct comparison with 

 house- martins and chimney -swifts. Eminently social in 

 their habits, they congregrate not only at the time of mi- 

 gration (then, indeed, least of all), and in the construction 

 of their homes, but sometimes alight in great flocks on the 

 reeds by tlie river-side and on the beach, where Sir William 

 Jardine saw them, "partly resting and w^ashing, and partly 

 feeding on a small fly, which was very abundant." Yet 

 you will occasionally notice stray individuals associating 

 with other swallows. 



The secret of the local distribution of the bank-swallows 

 lies in the presence or absence of vertical exposures of soil 

 suitable for them to penetrate for the burrows at the inner 

 end of wdiich the nest is placed. Firm sand, with no ad- 

 mixture of pebbles, is preferred, and in such an exposure, 

 be it sea-shore, river-bank, sand-pit, or railway-cutting, the 



