HIEUNDINIDJE. 283 



amongst these ^flocks are almost always a few Mar- 

 tins and Swallows. 



The Sand Martin differs considerably from the 

 other two species in the manner of building and the 

 locality in which it places its nest : this is always in 

 a hole, which the birds usually excavate for them- 

 selves : the place chosen for this excavation is gene- 

 rally in some steep sand-bank or side of a cliff, where 

 the nature of the soil allows them to work : about 

 here they generally choose the perpendicular side of 

 some quarry : the holes are made quite round, and 

 are generally some two or three feet deep from the 

 face of the bank or cliff: at the bottom of the hole 

 a slight nest is made of hay and feathers ; in places 

 nearer the sea, sea-weed appears to be the article 

 mostly made use of. In describing these holes all 

 writers appear to agree in saying to young bird- 

 nesters, "Beware of fleas," which abound in the 

 nest itself, and even round the mouth of the hole in 

 which it is placed. 



The food of the Sand Martin, like that of the 

 Swallow and House Martin, consists almost entirely 

 of insects, mostly flying ones. Yarrell, quoting 

 White's ' Selborne,' says the young are occasionally 

 fed with dragonflies as long as themselves. I have 

 never myself detected any of the Hirundinidae taking 

 dragonflies, or indeed anything much longer than a 

 May-fly, which is a very favourite food with all of 

 them. 



