APPENDIX 1. 



SERIES OF MAPS SHOWING THE INCIDENCE OF "GROUSE DISEASE" 



IN FORMER YEARS. 



By A. S. Leslie. 



The following series of maps has been prepared to show the localities in which "Grouse 

 Disease " has occurred during the last thirty-eight years, and the local distribution of the 

 various outbreaks. 



Scotland alone has been dealt with, for the information obtained from that country on 

 the subject of " G-rouse Disease " has always been fuller and more accurate than from 

 England. 



The series of maps commences with the year 1872, which, with 1873, will always be 

 notorious as the date of one of the most severe and widespread epidemics of " Grouse 

 Disease " ever known. An endeavour was made to go back to 1867, the year of another 

 serious outbreak which, especially in the Border districts, seems to have rivalled 1873 in 

 severity ; but at this earlier date the interest in the subject does not appear to have found 

 expression in the form of recorded observations, and the evidence is scanty and inconclusive.^ 



The records have been obtained by a systematic search of private memoirs and published 

 material, and of the latter the annual reports contained in the Field newspaper have been 

 of the utmost value. Most of the material was collected at an early stage of the investigation 

 when a sharp line of distinction was drawn between the severe outbreaks causing wide- 

 spread mortality and the mild or sporadic cases which were not then believed to be cases 

 of " Grouse Disease " in the true sense of the term. At that time the more serious attacks 

 were alone thought worthy of mention, and the earlier maps in consequence contain a smaller 

 number of recorded outbreaks than if a note had been made of every moor on which dead 

 birds had been picked up. As the work of the Inquiry proceeded it became evident that 

 the milder outbreaks of mortality were only different in degree, and not in kind, from the 

 more serious ones, and in the later maps every place is marked from which even a single 

 case of Strongylosis had been reported. 



The maps were prepared by Dr Wilson, and were arranged and reproduced after his 

 departure on the 1910 Antarctic Expedition. 



In the original maps each place from which " Disease " was reported was marked by 

 name, but for the present purpose it is thought undesirable to do more than indicate by 

 a dot the district in which the outbreak occurred. 



' But vide vol. i. chap. xxi. pp. 456-457. 



137 



