THE GROUSE IN HEALTH AND IN DISEASE 



35 



from this series of skins, is illustrated and elucidated by 

 many beautiful coloured plates. 



Many avenues were explored by the expert Staff in 

 search of some specific micro-organism which might be 

 demonstrable as the causa causans of " Grouse-Disease " ; but 

 for some time with negative results. The Parasites, large 

 and small, of the Blood and of the Alimentary Tract were 

 investigated by Dr Fantham and Dr Shipley respectively, 

 together with the Life-history of the parasitic and other 

 insects found in association with Grouse, or on ground fre- 

 quented by them ; and a great deal of most valuable informa- 

 tion was thus incidentally acquired. As regards the Disease 

 itself, two main theories had hitherto held the field. The one 

 supported by the great name of Klein, and at first favoured 

 by the Committee, attributed the specific cause of the Disease 

 to a bacillus of the colon group, and described its leading 

 characteristics as those of an acute, infectious, epidemic 

 pneumonia, causing death with very great rapidity, without 

 wasting, loss of plumage, or other external symptoms. 

 Cobbold, on the other hand, had declared as long ago as 1872, 

 that the cause of the disease was to be found solely in the 

 infestation of the caeca by a nematode worm of the genus 

 Strongylus (now Trichostrojigylus), with chronic irritation and 

 consequent functional loss in these organs, causing extreme 

 emaciation and death practically by starvation. 



The result of the Committee's investigations has been to 

 support Cobbold's theory in every respect. The specific 

 bacillus placed under suspicion by Klein was by Dr Selig- 

 mann demonstrated to be no other than B. coli migrating 

 post mortem from its proper sphere in the intestine into the 

 lungs and surrounding tissues. The Disease is at the same 

 time shown to be due to the presence of swarms of strongyles 

 in the caeca, and to be due to their presence alone, although 

 infestation by other parasites may affect the general health 

 of a host, and render it less resistant to the attack. When 

 the strongyle is present in overwhelming numbers, the 

 mucous membrane of the caeca does indeed become injured 

 to an extent that permits of the passage of a certain number 

 of the intestinal bacteria into the tissues of the liver and 



