﻿PENSILE AND CONCEALED NESTS. 



179 



the larks upon it : but the construction of all these nests 

 is upon the same general principle, however different 

 may be the materials employed., or the degree of its 

 elevation. 



(155.) Pensile nests are altogether peculiar to perch- 

 ing birds. They show many variations both of form 

 and construction ; but all these are very different from 

 those of the ordinary shape, both in the plan upon 

 which they are fabricated, and the mode by which they 

 are secured. The first indication of this fabric is seen 

 in the nest of our common wren, one of which was 

 erected this spring among the creepers trained round 

 our portico. Its shape is irregularly oval, and is so 

 disproportionate to the size of the bird, that its great- 

 est length measured near twelve inches j externally, it 

 seemed like a large bunch of withered leaves that had 

 accidentally got entangled among the slender and sinu- 

 ous stems of the clematis, and the thicker branches of 

 a sweet-brier. Upon looking at it more attentively, 

 however, a round opening appeared on the side, just 

 large enough to admit the entrance of its little architect. 

 Now a nest of this description has not a regular base, 

 and yet it cannot be termed pensile or suspended ; it 

 is evidently between the two, being as much supported 

 by the twigs above and on its sides, as by those upon 

 which it would seem to rest : perhaps we might call this 

 form a roofed nest, inasmuch as by the entrance being 

 lateral, its inhabitants are completely screened from the 

 weather, and from external observation. 

 " (156.) The change of nidification from ordinary nests 

 which are exposed, to those which are concealed or covered, 

 is marked by a beautiful gradation ; for those of some of 

 the tomtits are open above, and yet they are covered. 

 This union of styles is effected by the nest being fabri- 

 cated in a natural hole ; by which it is, as it were, 

 roofed in, without any additional labour of the bird. 

 The blue titmouse (Parus cceruleus) has for several years 

 built its nest within a crevice of an outside wall, caused 

 by the giving way and bulging out of the stucco ; the 

 n 2 



