DISEASES OF POULTRY. 169 



tacks small animals, but often swarms upon man if 

 its habitat is invaded. It punctures and even pene- 

 trates the skin, causing small swellings and almost 

 insupportable itching. Fowls are sometimes at- 

 tacked, the effects being most serious with chickens 

 hatched late in Summer or in the Autumn. The 

 parasites fix themselves to the skin at the base of the 

 feathers producing such intense irritation as to in- 

 duce epileptiform symptoms leading to death in a few 

 days. The mortality from this cause is sometimes 

 considerable. 



The red mite, or dermanyssus gallincs, is the most 

 common and most perniciously active of all the para- 

 sites which attack birds. It is from 1 -35 to 1 -40 inch 

 in length, yellowish, white, or dark red in color ac- 

 cording as it is fasting or is more or less filled with 

 blood. This parasite hides by day in the crevices and 

 corners of the buildings, nests, perches, floors, etc., 

 where it may be found in great clusters, and at night 

 the individuals composing these clusters scatter them - 

 selves over the birds, and by pricking the skin fill 

 themselves with blood. They are injurious not only 

 on account of the blood which is abstracted, but be- 

 cause of the itching, pain, and loss of rest which is a 

 necessary consequence of their activity. 



Young pigeons, chickens, and cage birds are the 

 greatest sufferers ; their skin becomes pale and blood - 

 less, they lose their usual vigor and alertness, become 

 emaciated, and may finally die from exhaustion. The 

 red mite is not usually found upon the fowls when 

 they are examined during the day, for its natural 

 tendency is to confine its foraging to the night, but 

 when it is allowed to multiply until very abundant 

 the fowls are infested both day and night, and it be- 



