6 Department Circular 79, U. S. Dept. of Agriculture. 



feeding, the mites may be found, attached in patches, several hundred 

 feeding in a space the size of a quarter. Since the adult remains on 

 the host it probably feeds intermittently, as it is easily disturbed and 

 runs about on the skin. Some mites readily leave an infested fowl, 

 when it is being handled, to crawl on the hands of a person. Mites 

 came off of a well-infested rooster placed in a box with an uninfested 

 hen and accumulated on the edges of the box. Many hungry mites 

 were found during the daytime on the edges of a box used as a nest. 

 When the box was touched large numbers would crawl quickly upon 

 the hand. If given a chance some of the mites will pierce tender skin. 

 One was observed attached to the back of a lady's hand. The lady 

 stated that the mites often bit her. 



HOSTS. 



In examining hosts the best method found was to put them in 

 a Mason jar and screw the cover down. If any mites are present 

 they will usually come to the cover of the jar or be found on the 

 glass or the surface of the host. Xo mites were found on the brown 

 thrush, song sparrow, blackbird, red-headed woodpecker, screech 

 owl, quail, or robin. Xone was found in a mouse nest or on a mole. 

 Mites were found only on poultry, in hen nests, or on loose feathers 

 in house or yard, and on English sparrows and in their nests. Xo 

 mites were found on English sparrows or in their nests on any farm 

 except one immediately adjoining the original infestation. Here 

 a few mites were found on flying English sparrows. It should be 

 explained that in the locality studied another mite was more or 

 less abundant in some of the English-sparrow nests examined. After 

 some study the common species and the tropical mite were easily 

 separated. The common species on the English sparrow does not 

 have the bilobed abdomen and the dorsal shield is more rounding at 

 the posterior end. 



CONTROL. 



Preliminary work. — In previous experiments sulphur, soap, and 

 water had proved so effective against the depluming mite (Cmmi- 

 docoptes gallinae Railliet) that this was the first remedy tried. A 

 hen having a heavy infestation was dipped in a mixture of 2 ounces 

 of sulphur, 1 ounce of soap, and 1 gallon of water. This was found 

 to be 100 per cent effective. Other treatments which were effective 

 in the preliminary work were: Dusting with sulphur, dusting with 

 pyrethrum, and dipping in a solution of 1 teaspoonful of 40 per 

 cent nicotine sulphate 'to 1 gallon of water and about one-third 

 ounce of soap. Mercurial ointment greatly reduced the numbers 

 but did not give 100 per cent efficiency. A solution of prepared lime- 



