"GROUSE DISEASE " STRONGYLOSIS 215 



contents and squeezing this flat between two glass slides, the 

 worms can be easily seen as transparent threads when held 

 up to the light. Innumerable ova of the worm also will be 

 found lying loose in the caecal contents. 



(2) The longitudinal ridges of the caeca, eight or nine in 

 number, are very much thickened, chiefly because the amount 

 of blood held by them is excessive, and the lining becomes 

 inflamed. 



(3) The swellings on the ridges which are conspicuous in a 

 healthy bird as greyish nodules, are far more conspicuous in a 

 case of Strongylosis when they become reddened and congested, 

 and seem to suffer to a greater extent and earlier than the 

 remainder of the ridges and the rest of the caecum. In some 

 cases, however, the time comes when every villus in the whole 

 gut seems to be intensely red and congested from one end to 

 the other. 



(4) There may be a very great deal of thickening of the 

 lining membrane from the swelling up of the villi and, after 

 post-mortem decay, the caecal membrane seen in water may 

 have the appearance of a furry rug. The contents of such 

 caeca are sometimes obviously blood-stained, and there seems 

 to be a bleeding form of the disease which results from the 

 sudden access to the gut of a very great number of young worms 

 all in a fully metamorphosed state. Such a case was produced 

 experimentally, and bleeding occurred in the caeca. There is 

 no apparent reason why under certain easily imagined circum- 

 stances the same thing might not happen in early spring-time 

 under natural conditions. 



(5) There may be appearances of recovery. In a good 

 many birds the caecal lining is dotted all over with minute 

 black pigment granules, in other words some of the villi show 

 no blood-vessels injected, but are filled with pigment granules 

 instead. These are sometimes so abundant as to colour the 

 gut. They lie in the villi in great numbers. 



It is possible that they result from previous chronic 

 congestion, and that there are circumstances under which 



