206 INSECTIVORdUS BIRDS 



day, and incubation takes a little over five weeks. As 

 incubation starts as soon as the egg is laid, the young ones 

 are ready to hatch at different times. The eggs are usually 

 of a delicate pink colour, especially when first laid, but the 

 pink colouring matter easily comes off, especially after the 

 egor has been taken out of the nest for some little time, and 

 leaves the white under surface exposed ; occasionally I have 

 found all the eggs in one mound pure white. The shell is 

 very fragile, and one reason why the eggs are placed on end 

 is evidently to sustain the weight of sand with which they 

 are covered ; the sand round the eggs is generally slightly 

 damp. Sometimes, when the parent bird is opening up the 

 mound, she scratches a hole in the top of one of the eggs ; 

 the sand then gets in, and, mixing with the contents, forms, 

 when dry, a compact sandy mass, completely filling the shell. 

 On one occasion I found five such eggs in one mound. 



" There has been much discussion as to whether the young 

 birds can make their own way out of the soil unaided by 

 their parents. In order to settle it I covered in with wire 

 netting a nest with several eggs in it, so that the parents 

 could not open it up, and found all the chickens, when they 

 came to maturity, dead in their shells. Then, again, on 

 taking the eggs from a nest you often find chickens in their 

 eggs which are ready to hatch, especially in the lower tier ; 

 so much so that, when opening the Qgg, you have to hold 

 the young bird firmly to prevent it escaping and running 

 away. Then, on other occasions, you find chickens near the 

 surface under the sand, apparently working their way out 

 unaided. The old birds open up the nest to a certain 

 extent daily at daybreak, and it is probable that any 

 chickens that may be ready to come out, especially in the 

 lower tiers, do so then. Moving the sand also prevents 

 it from becoming set. But the chickens that hatch from 



