Year three in the development of a computerized inventory of the mosses of Pennsylvania was designed to continue the efforts from the first two years of the project. In the initial efforts, pertinent literature on Pennsylvania mosses was entered into a database that included county reports on the distribution of the taxa. A preliminary list of "Infrequently Reported Mosses of Pennsylvania" was prepared, using any taxon at the species level or lower that was reported for six or fewer counties in the literature. A search of the major herbaria with Pennsylvanian material was initiated. A review of the reports from the first two years can be consulted for further details of the progress to date.