The countrywide epidemic of ringworm of the scalp which has been evident in New York for over two years has afforded an excellent opportunity for the further study of this disease. Signs of the epidemic were first observed in the spring of 1943. For the two years from July 1, 1943 to June 30, 1945 we have seen 312 patients with tinea capitis in the dermatology department of the New York Hospital. Most of these patients have been carefully studied both clinically and by laboratory methods. CLINICAL DATA ON RECENT CASES Contrary to our former observation1 that scalp infections due to Microsporon audouini and those due to Microsporon lanosum are of equal occurrence, it is now shown (table 1) that in New York City during the past two years scalp infections caused by M. audouini were nine times more common than those due to M. lanosum. Cases of M.