164r VETERINARY MEDICINE AND SURGERY. 



ized by absence of vesicles and by the formation of scurf around the hairs, 

 which in tliis form of ringworm break off short on being pulled. Tinea 

 tonsurans is contagious. Herpes circinatus is due to derangement of 

 the digestive organs, or the respiratory mucous membrane. 



Etiology. — Tinea tonsurans is produced by a vegetable parasite 

 which affects especially the hair follicles. The disease may commence in 

 any part. 



Symptoms. — In herpes, the vesicles, large or small, in ring form, in- 

 closing healthy skin, are typical (Fig. 77). In tinea, a white scaly scurf, 

 accompanied with staring of the hairs in the part affected, is the first 

 positive indication, followed by a thickened scurf with raised eminences. 

 This spreads rapidly in blotches over the neighboring parts, generally 

 assuming the form of rings, and the hair falls off. The appearance is so 

 peculiar that the disease cannot be mistaken by any one who has ever 

 seen a case. 



In ordinary cases, tinea is not very contagious, though generally sup- 

 posed to be so. It frequently, however, runs through stables, much in 

 the same way as influenza and other diseases, because similar causes pro- 

 duce similar effects. 



Treatment. — Herpes commonly requires little treatment. The 

 parts may be washed with lead liniment: 



Solution of subacetate of lead § ij. 



Olive oil § vii j. 



In tinea the hair should be clipped off round the blotches, and the parts 

 must be well washed as in mange, and apply: 



Iodide of potassium § i. 



Flowers of sulphur | ij. 



Iodine |ss. 



Lard |viij. 



Mix thoroughly. 



Or, 



Nitrate of silver gr. x. 



Lard 5 i. 



In either form of ringworm, a bran mash with a pound of boiled 

 linseed meal daily, in addition to the usual food for a few days, will 

 exert a beneficial influence on the skin; and an alterative consisting of: 



