12 Mr. Arthur E. tihij)Uy [Feb. 3, 



been dead for some time a certain bacterium, whose nature and life- 

 history he investigated. This bacterium is now recognised as one of 

 the Bacillus coli group, a widely spread group of bacteria which are 

 found universally in the alimentary tracts and which rapidly invade 

 the tissues of the body after death. At the time Klein was working 

 bacteriology was comparatively a new subject, and this invasion by 

 bacteria of the tissues at the time of and after death was not 

 appreciated. 



Klein's grouse disease was associated also with some congestion of 

 the lungs ; the windpipe was described as dark in colour, the air- 

 sacs contained blood, in the cavity of the lungs blood or some granu- 

 lar exudation occurred, the liver and kidneys were congested and soft, 

 and there was an exudation on the peritoneum. "We now, however, 

 know that many, if not all, of these appearances in the chief organs 

 of the body are but normal post-mortem changes and occur sooner 

 or later after death in birds which were perfectly healthy when killed. 

 Another feature attributed to the Klein's grouse disease was that its 

 onset was comparatively sudden, its course rapid, and according to 

 all observers it attacked healthy and plump birds. The present 

 Inquiry has not yet succeeded in coming across any sick or dead 

 birds which are plump or in good condition. All the grouse, and 

 they amount in number to nearly two thousand, which have been 

 investigated have been weighed, and in every case where there has 

 been any disease there has invariably been wasting ; the sick birds 

 are always thin, have lost flesh, and are in a poor condition. One 

 final feature of Klein's grouse disease is its seasonal incidence ; usually 

 it is said to occur with greatest virulence in the spring, to die down 

 during the summer, and to recur in a less virulent form in the 

 autumn. To this seasonal variation I shall return. 



Klein's grouse disease is still a matter of inquiry. During the 

 last five years, whilst the Commission has been prosecuting its 

 inquiries, this " disease " has frequently been reported, but on 

 investigation the characteristics enumerated above have not been 

 present ; still, the sportsman and the gamekeeper, who do not weigh 

 their grouse and seldom their evidence, and who are but imperfectly 

 acquainted with post-mortem changes, firmly believe in the existence 

 of this " disease," and it may be that it really exists, and that it is 

 the misfortune of the Inquiry that in their researches the investi- 

 gators have not come across it. 



If we now turn from what must seem rather negative criticism to 

 the more positive results attained by the investigation of the last 

 four years, we may begin by pointing out some of the difficulties 

 which confronted the Inquiry. 



In considering exceptions it is so immensely important to know 

 the rule. In studying disease our starting-point should be the 

 normal, the healthy ; yet until lately no one has studied the healthy 

 grouse, and indeed it is almost impossible to find a normal grouse, 



