THE AIR SAC MITE OF THE FOWL. 
17 
Holzendorff* alone of all authors consulted states that he 
has found these parasites buried in the liver, kidneys or other 
tissues, but while he denominates the parasite Cytoleichus Sar- 
coptoides he neither figures nor describes it and it seems very 
improbable that he really had to do with the mite in question. 
Although I am unable to define the manner, I am neverthe¬ 
less thoroughly convinced with Gerlach and Zundel that they do 
produce disease and death. Like Gerlach and Zundel I have 
made numerous autopsies on fowls in which there could be 
nothing discovered to account for disease or death except these 
parasites. 
Making a great number of autopsies on any and all affected 
fowls available for a period of one and one-half years some have 
been found which were quite free from this parasite but showed 
lesions which would clearly account for their ill health or death, 
others revealed more or less numerous mites along with a variety 
of lesions which could not with our present knowledge be attrib¬ 
uted to the presence of the parasites, while in most of the birds 
examined no cause other than the immense numbers of cyto- 
dites could be assigned. 
The symptoms of disease observed in those cases where no 
other evident cause than the presence of these parasites could be 
detected before or after death, while not wholly uniform, were 
quite as much so as could be expected when we consider the 
area over which the mites may be distributed and the variable 
symptoms possible for their location. Most constant and prom¬ 
inent of all symptoms was the profuse diarrhoea, the faeces 
being thin, yellowish-white, apparently granular, and very glu¬ 
tinous, adhering to the feathers about the anal opening in large 
masses. At the same time the bird becomes dull, drooping and 
feeble, although retaining a fair appetite and in some cases 
remaining fat until far advanced in the disease. The plumage 
gradually loses its lustre, becomes dirty, ragged looking, and 
much dishevelled. If the bird is left to itself it may move about 
fairly well, but if forced to run it quickly becomes exhausted, 
* Archives fiir wissenschaftliche und praktische Thierheilkunde. B. ii. p. 304. 
