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PRESIDENTIAL ADDRESS. 
arena—first reed, then bullrush, afterwards the common 
rush, and eventually grass, which is used for herbage, and, I 
am told, possesses extraordinary feeding qualities. The 
different style of farming adopted of late years has had a 
material influence upon many species of birds. The trans¬ 
formation of arable land into permanent pasture has 
been carried out to a very large extent in some parts, in the 
anticipation and hope that producing meat and dairy products 
will prove more profitable to the agriculturist than growing 
corn—hence the granivorous genera have been compelled 
to partially migrate to obtain necessary food, their place being 
occupied by soft-billed or insectivorous species; hence we find 
the sudden and abnormal increase of a certain species in one 
locality and decrease in another. I have often noticed that 
the country seems mapped out into districts or divisions, and 
that each has its complement of birds allotted to it. In case 
one of these divisions become depopulated from some cause 
or another, the void is immediately filled by some adjacent 
species, consequently we find the geographical range of a 
particular species often altered without any very definite 
reason, unless the hypothesis 1 have just given solves the 
problem. Again, the undue felling of timber throughout the 
country has a very great tendency to prevent the increase of 
bird life, as destroying means of shelter; also the laying or 
grubbing up of hedgerows. A good old-fashioned hedge of 
hazel or thorn, often yards through, with thick bottom of 
undergrowth—sacred spots to a sportsman—are objects 
of the past on a scientifically worked farm ; but such afforded 
excellent cover for birds to construct their nests in, and gave 
every chance of successfully rearing their brood without 
discovery by their various enemies. The reclaiming and 
enclosing of common, or so called waste land, has also helped 
to bring about this decrease. The natural enemies of birds 
are strong and numerous. I have seen them enumerated 
somewhat as follows :—Their own brethren, polecats, stoats, 
rats, cats, and hooded crows, to say nothing about boys, 
collectors, and the genus homo generally. Undoubtedly the 
vicissitudes of bird life are many, and at frequent periods the 
struggle for existence is both sharp and severe. The elements 
are important factors to be considered and taken into account 
wli encalculating destruction of life, as severe cold, continued 
frost, wind, or excessive wet, will deal death wholesale, 
especially if such calamitous conditions occur during the 
breeding season or migration. Last spring I had two instances 
brought most vividly under my notice. The first was the 
flooding of Eockcliffe Marsh, near Carlisle, where Skylarks, 
