During the summers of 1949, 1954, and 1960, large numbers of the snail Goniobasis livescens were collected from that portion of the Ocqueoc river which flows between Ocqueoc Lake and Lake Huron, in Presque Isle County, Michigan. Of these 3396 were dissected and the rectal areas of 749 (22.1%) found to contain larval treamtodes of the genus Proterometra. Numerous attempts to introduce these cercariae into fish resulted in recovery of a total of five adult specimens: one from the esophagus of Lepomis gibbosus (pumpkinseed sunfish) and two each from the esophagi of two Lepomis macrochirus (bluegill sunfish). These specimens differed from full-grown cercariae only in absence of the tail. Both larvae and adults do not correspond to any previously described species. The name Proterometra dickermani n. sp. is proposed for them.