A Revision of the Genus Lindsaea in the New World with Notes on allied Genera

The undertaking of the present study suggested itself to the author when, during the identification of ferns from Suriname with Posthumus’ treatment (1928), it became evident that the species of the genus Lindsaea were particularly poorly understood. As it proved to be impossible to elucidate the status of the species from that region only, without a survey of those from adjacent regions, it was decided that a revision of all New World species was indicated. It was possible to restrict the study largely to the representatives in that part ot the world, as there is not a single species occurring in both hemispheres. This, of course, does not imply that the Old World species have been completely left out of account; as a matter of fact, reference is made to them repeatedly in the present paper, especially where generic limits are concerned; but it would be altogether too big a task to complete a revision of the whole genus. Probably close to 3/4 of all species are restricted to the Asiatic-Oceanic region. No really complete revision of the genus has ever been given, apart from Hooker’s treatment in the Species Filicum (Vol. I, 1844/46), and Hooker & Baker’s Synopsis Filicum (1868, 1874). Diels (1902) gave only a superficial synopsis of the principal species. The situation is by no means better as far as the neotropical species only are concerned; the treatments are unsatisfactory, with ambiguous keys, as Baker’s (1870, in Flora Brasiliensis), and, as stipulated above, in Posthumus’ Ferns of Surinam, even, if only a small number of species arc involved, e.g. in Maxon’s Pteridophyta of Porto Rico (1926).