GROUSE DISEASE 195 



have a considerable fauna living both in and on 

 them. Grouse are in fact not birds, but in 

 a small way aviating Zoological Gardens. The 

 scientific members of the Inquiry have recorded 

 nine different species of insect or mite living 

 either amongst the feathers or on the skin of the 

 bird or in other ways associated closely with 

 the grouse, and no fewer than fifteen animal 

 parasites living in the alimentary canal, the 

 lungs, or other organs. Some of these are negli- 

 gible. They either exist in too small numbers 

 or infest but a very small percentage of birds ; 

 others, however, are found in about 95 per cent, 

 of the cases investigated, and two at least are 

 associated with grave disorders which often 

 terminate in death. 



The interest of the insects and mites which 

 live on the skin of the bird is that they very 

 likely form the second host of the tape-worms, 

 which undoubtedly do a certain amount of 

 harm to the lining of the alimentary canal. 

 There are, for instance, a couple of genera of 

 bird-lice, lively little creatures, which take cover 

 amongst the small feathers which, by the way, 

 form their arid diet like startled deer in the 



