132 POULTRY DISEASES AND THEIR TREATMENT. 



the liquid. The exact amount, however, must be determined 

 by the condition of the powder in each case. The liquid and 

 dry plaster should be thoroughly mixed and stirred so that the 

 liquid will be uniformly distributed through the mass of plas- 

 ter. When enough plaster has been added the resulting mix- 

 ture should be a dry, pinkish brown powder having a fairly 

 strong carbolic odor and a rather less pronounced gasoline 

 odor." 



"Do not use more plaster in mixing than is necessary to blot 

 up the liquid. This powder is to be worked into the feathers 

 of the birds affected with vermin. The bulk of the application 

 should be in the fluff around the vent and on the ventral side of 

 the body and in the fluff under the wings. Its efficiency, which 

 is greater than that of any other lice powder known to the 

 writer, can be very easily demonstrated by anyone to his own 

 satisfaction. Take a bird that is covered with lice and apply 

 the powder in the manner just described. After a lapse of 

 about a minute, shake the bird, loosening its feathers with the 

 fingers at the same time, over a clean piece of paper. Dead 

 and dying lice will drop on the paper in great numbers. Any- 

 one who will try this experiment will have no further doubt of 

 the wonderful efficiency and value of this powder." 



Next to the Lawry powder probably pure pyrethrum or Per- 

 sian insect powder is as cheap and effective as anything to be 

 had. 



A time-honored and effective treatment for lice, especially for 

 young chicks, is greasing. The grease most often used is lard 

 or sometimes lard and sulphur. TheJatter should not be used 

 for young chicks. The lard is applied with the finger to the 

 head, neck, under the wings and around the vent. Greasing is 

 a somewhat tedious but very effective treatment for lice, espe- 

 cially on young chicks, since lice usually attack them on the head 

 and neck. 



Prof. W. R. Graham, in conversation with one of the writers, 

 has strongly recommended the use of blue ointment (Unguen- 

 tum hydrargyri, U. S. P.) to rid birds of lice in cases where 

 individual treatment was demanded. 



B. MITES ACARINA. 



Eighteen species of mites are parasitic upon fowls. Only 4 

 of these are sufficiently injurious and widely distributed to be 



