The development of gametophytes in Bolbitis bernoullii, B. portoricensis and B. umbrosa (Lomariopsidaceae) is described and compared. Spores are monolete, ellipsoid with prominent winged perispore. Germination is of the Vittaria type and the prothallial development is of the Drynaria type. Collenchyma-like thickenings at the corners of the wing cells were not observed. Adult gametophytes are cordate with scarce marginal hairs near the shallow notch. Gametangia are of the common type found in homosporous leptosporangiate ferns. Bolbitis portoricensis develops the first leaf of the sporophyte after 6 to 8 months, with polocytic stomata. In B. portoricensis, vegetative propagation is present in old thalli 6 to 8 months after cultivation.