Plate 240.— POL V PODIUM DJCTVOPTEKIS. 



Family FILICES.] [Genus POLYPODIUM, Linn. 



Polypodium Dictyopteris, Mett. in Ann. Sci. Nat. iv (1861), 15. 



P. Cunninghamii, Uouk. Garden Ferns ad t. 30 (1862) ; Cheesem. Man. S .Z. Ft. 1U12. 



This very distinct little plant was first gathered by D'Urville in 1827 

 during the voyage of the French exploring-vessel " L'Astrolabe." D'Urville's 

 collections were worked out by the eminent l)otanist A. Richard, and published 

 in his " Essai d'une Flore de la Nouvelle Zelande." In this work he unfortu- 

 nately confounded the species now figured with the Australian P. attenuatum 

 (now known as P. Broivnii), and in this error he was followed by Allan 

 Cunningham and Raoul. No locality was given by Richard for D'Urville's 

 plant, but it was probably obtained at the Bay of Islands, or possibly in the 

 Hauraki Gulf. According to Sir W. J. Hooker ('" Iconcs Plantarum," t. 409) 

 it was next gathered by Allan Cunningham, although in the " Precursor " no 

 reference is made to any collector besides D'Urville. Since that time it has 

 been found to have a fairly general distribution in lowland districts in the 

 North Island, from the North Cape to Cook Strait. In the South Island it 

 is much more local. It has been gathered by myself near Nelson, Mr. Town- 

 son has found it to be fairly plentiful in the lower part of the Buller Valley, 

 Mr. Buchanan has recorded it from Marlborough, and Raoul collected it at 

 Akaroa. In this last locality, however, it does not seem to have been noticed 

 by any recent explorer. 



The very diverse views held by pteridologists as to the classification of 

 ferns are responsible for the frequent changes of nomenclature that P. Dictyop- 

 teris has suffered. Sir W. J. Hooker, in the " Genera Filicum," placed it, com- 

 bined with the Australian P. attenuatum, in Presl's genus Dictyopteris, most 

 of the species of which, however, belong to Aspidium. Mr. J. Smith appears 

 to have been the first to recognize that the New Zealand plant differed from 

 the Australian, and in 1846 placed the two species in a new genus which he 

 called Dictymia, and this view was adopted by Sir J. D. Hooker in the 

 "Flora Novas Zelandiae." In 1862 Sir W. J. Hooker, in his "Garden Ferns," 

 reduced the species to Polypodium, and, as Smith's specific name of lanceolata 

 was preoccupied, proposed that it should bear the title of P. Cunninghamii. 

 A few months earlier, how-ever, it had been published by Mettenius under the 

 name of P. Dictyopteris, which, under the law of priority of publication, 

 must now take precedence. 



P. Dictyopteris is usually found on the trunks of forest-trees or on 

 the faces of rocks, and has an altitudinal range from sea-level to 2,500 ft. 

 According to Mr. Baker, a plant collected by Mr. Moore on the Island of 

 Mallicola, New Hebrides, must be referred to the same species. 



Plate 246. Polypodium Dictyopteris, drawn from specimens collected at Mount Wellington, 

 near Auckland. Fig. 1, portion from tlie middle of the frond, showing two sori ( x 3) ; 2, two sporangia, 

 with the jointed hairs which usually accompany them (enlarged). 



