There is a group of cysts, sinuses and fistulas which are of dermatologic importance. While the cure of such lesions may be entirely within the province of the surgeon, their recognition frequently falls to the dermatologist, particularly those in which a clinical diagnosis is not immediately apparent. Further, their dermatologic appearance is at times so atypical that a correct diagnosis often depends on special knowledge of the various malformations and congenital anomalies of development which occur in certain regions of the body. It is worth while for the dermatologist to consider some of these lesions in order that errors in diagnosis and treatment may be avoided. EPIDERMAL CYST This condition is practically always mistakenly diagnosed as a sebaceous cyst or "wen." Various other names have been applied, such as atheroma, follicular cysts, squamous epithelial cysts and keratoma, the latter being a term used by Broders and Wilson1but which