EXTERNAL PARASITES 215 
The parasite is widely distributed throughout the world. Its 
depredations are more serious in warmer countries because of favor- 
able climatic conditions. 
Habits. During the daytime the mites collect in cracks, or under 
droppings and rubbish. They make their. Bey at night to the birds 
on the roost where they cause annoyance 
while engorging with blood. Occasion- 
ally mites will attack hens on the nest 
during the daytime. When engorged, 
the mite leaves the bird. Some mites 
that fail to become engorged the same 
night they gain access to the bird, will 
remain on the host during the following 
day or so. Thus hens have been found 
to carry as many as a hundred mites dur- 
ing the daytime. Eggs are laid in the 
places sheltering the mites, and hatch in 
two days or more depending upon the 5 a6 Piset ajaapbal: tae 
temperature. The larve hatching from of the chicken mite, unfed. 
the eggs shed their skins in about two Greatly enlarged. (Bishopp 
and Wood) 
days and become nymphs. After several 
engorgements and molts, the parasite reaches maturity. The whole 
life cycle is complete in a week. The parasites are not active in cold 
weather. In the absence of poultry, mites will remain alive in in- 
fested houses for four or ‘five months. Moisture seems to favor their 
longevity. 
Injury caused by mites. Excessive mite infestation has been 
held responsible for increase in cost of maintenance, decrease of 
ege laying and general unthriftiness. Sitting hens have been 
driven by the irritation, to abandon the nest. The attack of the 
mites rarely leaves a trace on the skin. 
Combating mites. In combating the pest, it is recommended 
that all interior fittings be removed so as to minimize the number of 
cracks in which mites could escape the action of the spray. If the 
house is of the older type, with built-in accessories such as perches and 
nests, everything should be torn out leaving merely the four bare 
walls. The whole house should be thoroughly swept and all rubbish 
removed. Kerosene oil, or kerosene emulsion constitute suitable 
agents for killing mites. One of these agents should be applied with 
a spray pump, particular care being taken to force the fluid into 
cracks. Since it is quite likely that some mites and eggs will 
