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16 nesting season is a dry one Grouse have been known to nest in very unsuitable places, such as the beds of burns and dried-up pools and water-courses — often with most disastrous results when the weather breaks.

But, if there has been no rain, the drowning theory must be discarded, and its place is taken by the drought theory; in other words, the fine, dry, warm, sunny weather which is credited with producing a healthy stock in a good year is the cause of their wholesale destruction in a bad year.

Nor do we know exactly what proportion of Grouse meet their fate from Vermin; that a certain number are killed by foxes, ravens, hoodie crows, stoats, weasels, and even gulls, may be admitted; but when we come to apportion the blame we again find ourselves without sufficient evidence to amount to proof. The subject of vermin is dealt with more fully in another part of the Report.

Occasionally it is found that old birds as well as young have disappeared, and when this happens it is customary to ascribe the cause to "Grouse Disease" amongst the adult birds, for it is well known that if a parent bird dies from disease or any other cause there is little chance of her brood surviving.

At a very early stage of the Inquiry it became evident that the loss of young stock on a large scale had never hitherto been properly accounted for, and required further investigation by the Committee.

The Committee believe they can offer a solution of this problem. During their Inquiry into the causes of mortality in Grouse they discovered a certain unicellular intestinal parasite, one of the Protozoa, a Coccidium, known as Eimeria avium, which in certain cases is most destructive to the young chick, but is rarely fatal to the adult bird; this Coccidium is fully described in another chapter of this Report. The discovery of the disease caused by this pathogenic organism and known as Coccidiosis justifies the view that when there has been extensive mortality amongst the young stock which cannot be accounted for in any other way, it is almost certain that the chicks have met their fate by this infantile complaint.

Coccidiosis as a disease of game birds and poultry is now being rapidly recognised in this country, and the disease is also being investigated in America.

Still there remains the difficulty that the dead bodies are not found in