TREE SPARROW. 23 



varies considerably, and depends a good deal on the 

 nature of the haunt. In some localities pollard willows 

 are the favourite nesting-places ; in others, holes in walls 

 and cliffs, as I found to be the case in St. Kilda, the 

 sides of old quarries, and even in the deserted nests of 

 Crows and Magpies. I have also taken the nest from a 

 hole in the branch of an oak tree. In other cases, a site 

 is selected under the eaves of a building, or even in a 

 hole in the thatch. In some few instances (when in old 

 nests of Crows) the nest is domed and well made, but 

 as a rule it is a slovenly structure, like that of all or 

 most hole-builders, cup-shaped, and made of dry grass, 

 straws, and roots, and warmly lined with feathers, and, 

 less frequently, wool and hair. I have noticed that this 

 species becomes very demonstrative when disturbed 

 at the nest, and evinces much more anxiety than the 

 House Sparrow usually does. Both male and female 

 assist in the construction of the nest, in which as many 

 as three broods are sometimes reared. The Tree 

 Sparrow is nothing near so gregarious as the House 

 Sparrow, and each pair of birds keep much to themselves. 

 RANGE OF EGG COLOURATION AND MEASUREMENT : 

 The eggs of the Tree Sparrow are from four to six in 

 number, and vary considerably in colour. Even in the 

 same clutch one egg is often found much lighter in 

 colour than the rest. They are grayish-white, or white 

 with a faint blue tinge in ground colour, spotted and 

 speckled with rich brown and grayish-brown, and with 

 underlying markings of violet-gray. On some examples 

 a few dark lines or streaks occur. The markings are 

 generally so thickly distributed over the surface as to 

 hide almost all trace of the pale ground colour ; but on 

 others, where the spots are larger and fewer, this is 

 not the case, and then the gray underlying markings 

 are also more conspicuous. Average measurement, 79 



