under the skin. The joints of the feet appear affected, and the foot and
leg become enlarged, roughened and scaly.

_Depluming scabies_ is caused by _Sarcoptes laevis var. gallinae_. This
mite causes the feathers to break off at the surface of the skin. Masses of
epidermic scales may form around the broken ends of the feathers. The
diagnosis can be confirmed by examining the skin lesions and finding the
mite.

_The air sac mite_ (_Cytodites nudus_) may cause sufficient irritation to
the mucous membrane lining the air sacs to seriously obstruct the air
passages with mucus, or produce death from exhaustion. A post-mortem
examination of a fowl that has died of this disease shows the mites on the
surface of the lining membrane of the air-sacs. They appear as a white or
yellow dust.

TREATMENT OF POULTRY DISEASES CAUSED BY MITES.--Diseases of poultry caused
by mites may be prevented by quarantining all recently purchased birds for
a period of from two to four weeks, and by keeping the poultry houses
clean. Birds that are found infested with parasites should be destroyed or
returned. In case the bird is valuable and suffering from external
parasites only, it should be given the necessary treatment.

_Red mites may be destroyed_ by thoroughly cleaning the poultry house, and
spraying the roosts, nests, walls and floor with a three per cent water
solution of liquor cresolis compositus. This should be repeated twice a
week for two weeks.

_Scaly-leg may be treated_ by applying a penetrating oil to the feet and
lower part of the leg. It is advisable to first remove the scales by