Although inclusion conjunctivitis in the infant was defined as an entity as early as 1911 by Lindner,1 general textbook recognition of its widespread occurrence and of its importance as one of the types of ophthalmia neonatorum did not obtain until recently. There was, furthermore, a delay in the identification of the not uncommon infection of the adult with that of the infant, although a nontrachomatous conjunctivitis with epithelial cell inclusions epidemic among bathers in certain public pools was recognized by Huntemüller and Paderstein2 in 1913. This delay in identifying the disease in the infant and that in the adult may have been due to differences in clinical appearance, the latter disease being characteristically follicular and milder than the former, which is an acute papillary conjunctivitis. At present, however, as a result of the filtration experiments of Gebb,3 Botteri,4 Thygeson,5 Tilden and Gifford6 and Julianelle,