THE SAND MARTIN 



323 



and is lined with feathers and fine grass. The eggs are generally four 

 or five in number, and the bird rears two broods in the course of the 

 year. 



The pretty little Sand Martin is, in spite of its sober plumage and 

 diminutive form, a very interesting bird, and one which adds much to 

 the liveliness of any spot where it may take up its abode. 



In size it is less than any other of the British Hirundinidse, being 

 less than five inches in total length. The color of this bird is very 

 simple, the general tint of the entire upper surface of the head and 

 body being a soft brown, relieved from too great uniformity by the sooty 

 black quill feathers of the wings and tail. The under surface is pure 

 white, with the exception of a band of brown across the upper part of 



The Sand Martin (Cotile riparia). 



the chest. The young bird possesses a lighter plumage than the adult, 

 owing to the yellowish white tips of the back, tertiaries, and upper 

 coverts. The beak is dark brown, and the eyes hazel. 



Although its little beak and slender claws would seem at first sight 

 to be utterly inadequate for the performance of miner's work, the Sand 

 Martin is in its way as good a tunnel-driver as the mole or the rat, and 

 can manage to dig a burrow of considerable depth. The soil which it 

 most loves is light sandstone, because the labor which is expended in the 

 tunnelling is very little more than that which would be required for 

 softer soils, and the sides of its burrow are sufficiently firm to escape 

 the likelihood of breaking down. 



The depth of the burrow is extremely variable, some tunnels being 



