NON-INDIGE.\OUS BRITISH BIRDS. 205 



woods, but in woods where the ground is dry ; in tree- 

 less districts the bird breeds amongst reeds, and in 

 Egypt, according to HeugHn, sometimes even in gardens. 

 A large colony visited by Mr. Gurney in Algeria was 

 situated in a bed of dead tamarisks only a few feet 

 above the water. The nest is flat, shallow, and made 

 of sticks, when in trees or bushes, and composed of 

 dead reeds and other aquatic refuse when in marshes 

 and swamps where trees are absent. In its behaviour 

 at the nest the Buff-backed Heron does not differ from 

 its allies, rising in a slow, awkward manner, and hover- 

 ing noiselessly above the colony until the alarm subsides. 



Range of egg colouration and measurement : 

 The eggs of the Buff-backed Heron are from three to 

 five in number. They are chalky in texture, oval in 

 form, without polish, and almost white, with a scarcely 

 perceptible tinge of bluish-green. Average measurement, 

 I'S inch in length, by 1*3 inch in breadth. The duration 

 of the period of incubation is unknown, as is also which 

 sex performs the duty. 



Diagnostic characters : The size combined with 

 the pale colour sufficiently distinguish the eggs of the 

 Buff-backed Heron from those of other European 

 species. Unfortunately, however, they cannot be dis- 

 tinguished from eggs of Montagu's Harrier. Except in 

 the Spanish peninsula, however, the breeding areas of 

 these two birds do not impinge. 



