Su PARASITOLOGY. 
Fig. 19—PsororTes CoMMUNIS, variety Bovis. Photomicrograph. 
1 and 2, Females. a, Head parts. 
b, Legs. c, body. 
ally becoming thin in flesh, and later emaciated. 
PsoROPTES CoMMuNIS, variety Ovis (Ovis—sheep). 
ffistory.—Widely distributed. Found in western 
and southwestern parts of the United States; also in 
France, Germany, Asia, Australia and Mexico. 
Animal Infested.—This is the common scab para- 
site of the sheep. 
Condition Produced; Symptoms.—In watching a 
bunch of sheep that have recently become infested, 
it will be noted that they are restless; that they will 
bite themselves; that bunches of wool will become 
loosened; possibly some saliva will be noted at this 
point. If the skin be examined with the aid of a 
hand lens, or if a scraping be made with a knife 
(care must be taken to get close to the skin), the 
parasite will be found. Or, if the scraping be placed 
inaclear glass bottle and the bottle set in the sun- 
