106 BRITISH BIRDS. [vol. vii. 



The following observations upon the nesting of this 

 species, will illustrate a state of affairs which I have 

 noticed in many instances : — 



I. — There were five eggs in the nest on April 4th, on the 5th there 

 were two newly hatched chicks and three eggs. The same condition 

 of affairs existed on the 6th. On the 7th there were three young and 

 two eggs. These eggs did not hatch. All went well until April 11th, 

 when the youngest bird, hatched en the 7th, was found to be dead. 



II. — On April 11th there were three eggs in the nest. On the 12th 

 there were two eggs and one young bird. On the I.Sth two young 

 and one egg. No change on the 14th. On the l£th the last egg had 

 hatched. On April 21st the smallest young one was dead. 



III. — On April 15th this nest held five eggs. On the 16th one egg 

 had hatched. On the 17th there were two j^oung and three eggs. 

 On the 18th three young and two eggs ; 19th, four young, one egg ; 

 20th, ditto ; 21st, five young. The nest was not examined again until 

 April 24th, when the two smallest chicks were dead ; one of them had 

 disappeared, the other was lying under the three survivors. On 

 the 26th the smallest of these three was lying dead under the two 

 larger birds. 



IV. — On April 5th this nest held one yoimg bird. On the 6th three 

 young ; on the 7th four young. On April 19th there were only three 

 young left ; the smallest bird having disappeared. 



It is seen from these examples, which are (according 

 to my experience) typical of the state of affairs prevalent 

 in the nesting-economy of the Rook, and which were 

 observed under normal circumstances, that the young 

 which emerged from the last laid eggs were the in- 

 dividuals which perished. This is undoubtedly brought 

 about by the great variation in the size of the nestlings, 

 consequent on the difference in age. The first chick 

 hatched of a clutch of five eggs has gained greatly in 

 bulk by the time the nestling from the last egg laid 

 has emerged ; the natural result of this is that when 

 the parent comes with a supply of food for the sus- 

 tenance of its offspring, the oldest bird is the one 

 whose head is upstretched to meet the proferred morsel 

 in the most prominent manner, and this chick has the 

 greatest strength with which to press for food ; even 

 where the parent bird is desirous of apportioning the 

 food in an equable manner (and this desire is evidently 

 not strong in many species), it can be no easy matter 

 to ensure the youngest bird its fair share of supplies, 



