SJdn Diseases. 275 



other. It is especially common in winter or spring, anrl 

 occurs as round bald spots on the face or elsewhere 

 covered with white scales, and surrounded by a ring of 

 bristly, broken hairs, or split hairs with scabs around the 

 roots and some eruption on the skin. Soon this ring of 

 broken hairs is shed and a wider bristly ring is formed. 

 Among the naked eye characters the breaking and splitting 

 of hairs in the ring, and the perfect baldness of the central 



Fig. 42. 



Fig. 42 — Hairs with spores of Trichophyton Tonsurans. From the horse. 



— Megnin. 



part are the most significant. Chloroform bleaches the 

 affected hairs, while the sound ones are unaffected. The 

 microscopic appearances are the presence in the hairs and 

 hair follicles of a vegetable parasite {trichophyton tonsu- 

 rans.) 



Treatment. Shave the hairs from the affected part, or 

 better, pull them out with a pair of pincers and paint with 

 tincture of iodine, or a solution of corrosive subhmate (40 

 grains to 1 pt. of water), or of bisulphite of soda (|- oz. to 

 Ipt.) 



HONEY-COMB EINGWOKM:. PAVUS. 



Common in cattle, dogs, cats, rabbits and chickens, as well 

 as in children [scaM-head). It shows the same general ap- 

 pearance of baldness advancing from a centre, which is 

 described above, but a cup-shaped yellowish scab results 

 which has obtained for it the name. The parasite (Acho- 

 rion ScliCnleini) appears to be but another form of the 

 fungus of ringworm affected by its conditions of growth 

 and especially by the weak or unhealthy condition of the 

 Uost. Treat as for common ringworm. 



