The diseases included under this heading are lichen and prurigo.

Lichen is a papular disease, which is described by Williams as the papular form of eczema. It commences by an eruption of small papules, from which a fluid is discharged, and afterwards becomes dry and forms a crust. The disease is most frequently seen on the legs of horses, along the course of the flexor tendons. The exudation which occurs round the hair follicle glues the hairs together, forming small tufts, and gives to the legs the appearance of being covered with tails of rats; in fact, the disease is commonly called "rat tails".

Treatment would be precisely the same as that prescribed for the pustular form of eczema.