EXTERNAL PARASITES 



71 



the condition of tlie 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 plaster. When 

 enough plaster has been added the resulting mixture 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 affrcted 

 with vermin. The bulk of the application should be in the fluff 

 around the vent and on the lower side of the body and in the fluff 

 under the wings. Its efficiency, wiiich is greater than that of any 



Fig. 26. Inexpensive, Durable Spray Pump. 



other louse powder known to the writer, can be very easily demon- 

 strated by anyone to his owm satisfaction. Take a bird that is 

 covered with lice and apply the powder in the manner just de- 

 scribed. 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 num- 

 bers. Anyone who will try this experiment will have no further 

 doubt of the wonderful efficiency and value of this powder. 



After freeing the flock from lice, care should be exercised 

 that a reinfestation is not brought about by the introduction 

 of lousv birds. 



