A total of 740 echeneid fishes comprising 4 species (Remora osteochir, R. remora, R. brachyptera and Phtheilichthys lineatus), were collected in Hawaiian waters throughout May and June, 1979. The latter three species were found attached to a number of hosts, including sharks, billfishes and floats, but all R. osteochir collected (208 specimens) were attached only to billfishes. The abdomen in 40 female specimens of R. osteochir was greatly distended, indicating a fully formed ovary. In many cases, a mature pair of R. osteochir was attached to a single billfish, suggesting a one to one mating habit. Unfertilized eggs were colorless, translucent, free floating and nearly spherical, the diameter varying from 1.44 to 1.52mm (average 1.49mm). A single spherical oil globule measuring 330-380μm (average 350μm) was found in the yolk. The surface of the chorion was finely wrinkled. Approximately 30, 000, 27, 500 and 8100 eggs were found in 278.0mm SL, 215.0mm SL and 163.5mm SL specimens, respectively.