DISEASES OF THE SKIN. 331 



bleed or become ulcers, or they may run together, and 

 large patches of skin may thus be involved in a common 

 condition. If this state of things continues, deep sores 

 may form. 



It may be that from the first the inflammatory condi- 

 tion may be somewhat different ; there may be no vesicles, 

 pustules, or exudations, but a redness of the skin with dry 

 exfoliation of the epithelium in a sort of coarse dandruff. 

 Such a condition is often termed pityriasis rulra, and 

 may occur over the whole body. 



Again, there may be an eruption of papules small and 

 more readily felt than seen, each one being distinct and 

 giving a " shotty feel," a condition known as prurigo. 



Generally, in the less acute (subacute) forms there is 

 little exudation, etc. Chronic conditions are marked by 

 thickening, loss of flexibility, a tendency to crack, exten- 

 sive loss of hair, etc. 



Since the hair follicles may be involved, loss of hair is 

 very common in all forms of skin disease. The exact 

 course of the inflammation is determined not alone by the 

 cause, but depends on whether the dog is long-haired or 

 the reverse, the nature of the treatment, and his individu- 

 ality. 



More or less tenderness or actual pain, itchiness, irri- 

 tability of temper, possibly restlessness, even to the point 

 of sleeplessness in extreme cases, with corresponding failure 

 in the general health, are common. However, in all such 

 matters there is the greatest range of variability. 



Diagnosis. It is highly important to distinguish be- 

 tween parasitic inflammations of the skin and those not 



due to this cause. The principal diseases of the skin de- 

 23 



