250 veti-:rin'akv I'ATiKir.ocv. 



the Ijldiid Ixniig- observed through the transparent ocular struc- 

 ture. The so-called "Wall-eyed" horses have little if any pig- 

 ment in the choroid tunic, and frequently they have depigmented 

 localized cutan'^ous areas. 



Depigmentation is probably never generalized. I'ermanent 

 localized depigmentation, lencoderma or vitiligo, is a character- 

 istic symptom affecting the external genitals of horses afflicted 

 with dourine. It is also observed in cicatrices resulting from 

 burns or extensive operative procedure. Surgeons usually make 

 incisions in an oblicpie direction in order that th.e hair in the ad- 

 jacent skin ma^■ cover the scar. Scars are usually devoid oi hair, 

 and when hair is present it mav lack piginent. The application 

 of some medicaments on the skin of some animals causes the 

 hair to lose its pigment. 



Temporary depigmentation is evident after an attack of coi- 

 tal exanthema, vaginitis accompanied by an ichorous discliarge, 

 and bv man\' other conditions characterized by erosion or necro- 

 sis of cutaneous tissue. 



Effects. — The absence of pigment is of no serious conse- 

 c]uence except in some animals. Hogs that are white skinned 

 cannot be raised in some localities because of the effects of the 

 sunliglit. Depigmentatii m of the choruid is also of some conse- 

 quence, because the eye is exposed to the effects of excessive 

 light. 



