Electron Microscopic Observations on the Lesion of Elastosis Perforans Serpiginosa**From the Medical and Dermatology Services, Massachusetts General Hospital, and the Departments of Medicine and Dermatology, Harvard Medical School, Boston, Massachusetts.This is Publication No. 274 from the Robert W. Lovett Memorial Unit for the Study of Crippling Disease. Support of these investigations has been received in large part from the National Institute of Arthritis and Metabolic Diseases, U.S.P.H.S., (Grants #A10647 and A-3785), and the Eli Lilly Company.