1. An organism was isolated and studied in pure cultures from cases of conjunctivitis accompanied by the so called trachoma body inclusions, as well as from a case of old trachoma without inclusions.
2. This organism was not found in the cultures made from other forms of conjunctivitis in which the inclusions were absent.
3. The organism presents the morphological features characteristic of so called trachoma bodies. It undergoes an early transformation, during which the forms known as initial bodies appear, and a later change, during which forms resembling elementary granules arise, while certain intermediate forms between these occur simultaneously.
4. No definite cell inclusions could be produced in monkeys by inoculating pure cultures of the organism.
5. The cultivation of this organism from a case of trachoma without the cell inclusions, together with the previously ascertained fact that the inclusions can be produced in suitable animals by inoculating such material directly from a human case, suggests the possibility of the organism being still present in such cases of trachoma, although not in the form of cell inclusions.
6. The facts presented justify the statement that by a suitable method an organism resembling the various important stages of the trachoma bodies and totally distinct from the gonococcus has been obtained in a living condition, capable of indefinite cultivation from cases of human trachoma and inclusion conjunctivitis. Whether the organism and trachoma bodies are identical cannot be positively stated at present. But the way is now opened to determine this point, as well as the specificity of the trachoma bodies.