Disease," from a field observer's point of view, had been ascertained. Even at this date the Committee were of opinion that they had discovered the principal causes of mortality amongst Grouse; but until they had further confirmed their suspicions they decided not to publish anything in the nature of results. It was at this stage that an impatient public and the necessity to stimulate dilatory subscribers forced upon the Committee the necessity of publishing some account of their progress, and the Interim Report issued in August 1908 was the outcome of this demand. The Interim Report contained an account of the work done by the Committee up to date, but omitted all reference to the results which had only been achieved in part.
During the second or research stage of the investigation the following special points were studied: (l) The life history of the Trichostrongylus pergracilis, which the Committee believed to be the immediate cause of "Grouse Disease"; (2) The life history of the other internal parasites of Grouse; (3) The protozoal parasites infecting the alimentary tract and blood of Grouse; (4) The bacteriology of Grouse; (5) The various insects found on the moors both from the point of view of insect-borne disease and from the point of view of food; (6) The questions afiecting the food supply of Grouse, including the management of heather land, causes of destruction of heather, e.g., frost, heather-beetle, etc.
These lines of research were diligently followed up by the members of the Committee's Scientific Staff during the last three years of the Inquiry—the work entailed long series of experiments carried out upon the open moor, in the laboratory, or at the Frimley observation area. The results have been unexpectedly conclusive, considering the short time available for so great a task.
The Committee consider that although their immediate object has been achieved, viz., the elucidation of the causes of "Grouse Disease," the present Inquiry has scarcely crossed the threshold of the investigation into the general pathology of birds, and there is still a large amount of work which might be profitably under- taken. The most important department of the research, so far at least as relates to mortality amongst adult Grouse, was the investigation of the life history of the strongyle threadworm. The work was rendered difficult owing to the small size of this parasite, but thanks to the efforts of Dr Wilson, Dr Shipley, and Dr Leiper, we are now in a position to speak with something approaching certainty on the subject. These gentlemen have worked at the subject for more than three years, and have not only ascertained the life cycle through which this worm passes, but have discovered the conditions which are favourable or preju-
