FURUNCULAR ERUPTIONS. 151 



chronic cases the system is supported, the diseased tissues 

 are incised, and caustics used. 



SCORBUTIC ERUPTIONS. 



Still following out Mr Wilson's classification of skin dis- 

 eases, I must here notice that condition of the system "in 

 which blood is effused in the substance of and beneath the 

 skin. There is but one form of this disease which is seen in 

 the horse, and which has been described under the head of 





 PURPURA H^EMORRHAGICA. 



This disease, though implicating the skin above all other 

 parts or textures in the body, is due to a condition of blood 

 favourable to passive haemorrhage, or physical transudation 

 of the constituents of the blood through the coats of the 

 vessels. The disease was first described by the late Mr John 

 Field under the title Pyrrecchymosis, and as Mr Field's re- 

 marks on the subject were quite original, and are often re- 

 ferred to, I here reproduce them. 



" So designated by Dr Willan, where petechial spots 

 appear on the skin, with or without fever. 



"Affects the skin, mucous membranes, cellular tissue, par- 

 enchyma of internal organs, as lungs and kidneys; also issues 

 from the brain, from between the coats of the intestines, and 

 from the mucous cavities of the body. 



"Varieties. Purpura simplex, purpura hsemorrhagica, 

 and purpura urticans, resolve themselves into the acute and 

 sub-acute in the horse, both proceeding rapidly either to a 

 favourable or unfavourable result. 



''Symptoms. Effusions beneath the skin, of irregular 

 form, on the thighs or fore-arms, or under-part of abdomen, 

 gradually or suddenly increasing; petechial spots on the 

 Schneiderian membrane; swellings of nose or lips; ecchy- 



