•,2S RADIATION' inOLOOV 



(1891) tTlier den lOinfhiss cles Lichtes auf d'w. Haut. Hcitr. OpthaliTiol., Wit 



ami Coiiii)any, Lcipzin. Pp. JiW 151) (also llynira: Fcslhaiid Xr. '.i, 188'.»). 

 Witli, C (li)20) Stiuiies cm tliccfTcct of li^lit on vitiligo, lirit..). Dermatol. Syphilis, 



;J2: 145-155. 

 Woodruff, C. E. (1905) The effects of troijical liKlit on white men. Rebinan Com- 

 pany, Now ^■ork. 



Manuscript received by the editor July 2(), 11)51. 



ADDENDUM 



Recent experiments in this laboratory indicate that the erythemal 

 threshold, primary pigmentation, and thickening of the epidermis, do not 

 exhibit photorecovery. That is, illumination with "visible" Hght after 

 exposure to ultraviolet does not affect these manifestations of sunburn. 



