324 THE HOUSE MARTIN. 



only eighteen inches or two feet deep, while others run to a depth of 

 nearly five feet. During some five years' experience and constant 

 watching of these birds in Derbyshire, I generally found that the hand 

 could reach to the end of the burrows and remove the eggs, provided 

 that the birds had not been forced to change the direction of the tunnel 

 by the intervention of a stone or a piece of rock too hard for their bills 

 to penetrate. 



As is o-enerally the case with burrowing birds, the Sand Martin takes 

 very little trouble about the construction of its nest, but contents itself 

 with laying down a small handful of various soft substances, such as 

 moss, hay, and feathers. The eggs are very small and fragile, and are 

 not easily removed from the burrow without being fractured. Their 

 color, when freshly laid, is a delicate semi-transparent pink, which 

 darkens to a dull opaque gray when incubation has proceeded to some 

 extent, and changes to a beautiful white when the contents are removed 

 from the shell. Their number is from four to six. 



The food of this bird is composed of insects, and, in spite of the 

 small dimensions of the little creature, it will pursue, capture, and eat 

 insects of considerable dimensions and strength of wing, such as wasps 

 and dragon-flies. Gnats and similar insects, however, form the staple 

 of its diet. 



This bird generally makes its appearance in England about the begin- 

 ning of April, and has even been noticed before the end of March, 

 so that its arrival is earlier than that of the swallow or martin. It 

 departs about the beginning of September, and like other of the British 

 Hirundinidse, makes its way to Africa, where it remains until the 

 succeeding year. 



Resembling the common swallow in habits and general appearance, 

 the House Martin may easily be distinguished from that bird by the 

 large white patch upon the upper tail-coverts, a peculiarity which is 

 even more notable when the bird is engaged in flight than when it is 

 seated on the ground or clinging to its nest. In the dusk of evening 

 the Martins may often be seen flying about at so late an hour that their 

 bodies are almost invisible in the dim and fading twilight, and their 

 presence is only indicated by the white patches upon their backs, which 

 reflect every fading ray and bear a singular resemblance to white moths 

 or butterflies darting through the air. 



This beautiful little bird is found in all parts of England, and is 

 equally fiimiliar with the swallow and sand martin. It places its clay- 

 l)uilt nest principally under the shelter afforded by human habitations, 

 and becomes so trustful and fearless that it will often fix its nest close 

 to a window, and will rear its young without being dismayed at the near 

 j)resence of human beings. 



The nests of this species are extremely variable in shape and size, no 



