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iu tlie following order : — groin, slieath, axillas, Lelow the belly, 

 below the neck and throat, sides of neck and shoulders, between 

 the toes, legs, face, sides of chest, back. Another writer says 

 it generally begins in the axillary or inguinal region and 

 thence extends to the neck, head, shoulder, arm, forearm, and 

 anterior costal region, thence passing to the flanks, back, coccyx, 

 and so on. The parasites cause severe pruritus, the itching 

 being greatest at sunset (Haslam). The animal nibbles, 

 scratches, and bites the seat of irritation, and rubs himself 

 against trees whenever possible, enjoying the friction as giving 

 him temporary relief, but perhaps in scratching conveying para- 

 sites to fresh parts which thus become secondarily affected, 

 '' again, much like a dog with chorea, throwing first one fore- 

 leg and then the other in a spasmodic manner to the front, " as 

 Clayton informs us and goes on to point out that others as 

 they progress rub one thigh against the other. In the parts 

 which have longest been affected the hair is lost and the skin 

 becomes irregularly furrowed, and in that condition known as 

 Psoriasis ; it is coriaceous, squamous, and chronically altered 

 throughout its thickuess, often covered with crusts of an offensive 

 odour ; some affected parts of the skin become black, but this is 

 considered, by Martin, an indication that the disease is being 

 conquered. The gradual spread of the disorder and the regular 

 series of changes through which the several affected parts pass 

 is rather diagnostic of this disease. The acari travel about, and 

 may be seen among the debris, crusts, and dirt on the skin. The 

 affected parts become torn and ulcerated by the teeth and hoof 

 nails of the animal ; sometimes the acari are found in the subcu- 

 taneous areolar and muscular tissues of the abdominal walls, and 

 in neglected cases peritonitis may be caused by the great inflam- 

 mation in the neighbourhood, as Haslam has pointed out, and 

 he enuraei-ates Septicgeraia and Pyaemia among the results of this 

 disorder. The most serious result in relation to working power 

 is the debility and loss of condition entailed by the continuous 

 irritation of the unfortunate animals ; this, in some cases, culmin- 

 ates in diarrhoea, a precursor of death. In this way a force 

 may become crippled as regards Transport, and its expense 



