Studies on Pacific Ferns, Part IV 
The Pteridophyte Flora of Pitcairn Island 
G. Brownlie 1 
Although the ferns of southeastern Poly- 
nesia have been described in several papers, no 
separate list has previously been provided for 
Pitcairn Island. The present paper outlines the 
details of a collection made there by Mr. W. H. 
Lintott of the Botany Department of the Uni- 
versity of Canterbury, and includes mention of 
other collections where these were available. 
When the changes which have occurred in the 
indigenous vegetation are considered, it is re- 
markable that, as well as finding all the other 
species noted earlier, one species not previously 
recorded from Pitcairn is included in the most 
recent collection. 
Of the 20 species listed, 15 are widespread 
throughout Polynesia, and 2 others are prob- 
ably local derivatives of similarly widespread 
species. This large group represents the dom- 
inant Malay-Papuan element found in decreas- 
ing numbers of species from west to east in the 
tropical Pacific. Of the remaining 3, 1 species 
of Asplenium and 1 of Trichomanes are found 
in S.E. Polynesia and New Zealand, and are 
the only ones to which Copeland’s ( 1938) ideas 
of an Austral group can be applied. The single 
species of Cyathea is related to ferns found in 
Rapa and the Society Islands. There are only 2 
species recognised as endemics, and each of 
these may in fact be better regarded as varieties. 
Viewed as a whole, the pteridophyte flora of 
this region, Pitcairn, Rapa, and the Australs, 
appears to be merely an extension of that of the 
Society Islands. 
Abbreviations: C, Department of Botany, 
University of Canterbury; W, Dominion Mu- 
seum, Wellington; S, Department of Agricul- 
ture, Suva, Fiji; K, The Herbarium, Royal Bo- 
tanic Gardens, Kew. 
1 Department of Botany, University of Canterbury, 
Christchurch, New Zealand. Manuscript received April 
25, I960. 
PSILOTACEAE 
Psilotum nudum ( L. ) Grisebach 
Pendant on trees and shady rocks; not com- 
mon. Widely distributed throughout Polynesia. 
Lintott 167a and 167b (C), Williams 3068 
( W ) , Twyford S.P. 129 (S). 
MARATTIACEAE 
Angiopteris chauliodonta Copeland 
On damp hillsides in dense shade. I doubt- 
fully retain this as a distinct species, and it may 
be only a local form in which the sterile apices 
of the pinnules are more toothed than is usual 
in A. eve eta. 
Lintott 150 (C), Twyford S.P. 130 (S). 
GLEICHENIACEAE 
Dicranopteris linearis (Burm.) Und. 
Gleichenia linearis (Burm.) Clark. Brown, 
B.P. Bishop Mus. Bull. 89, 97, 1931. 
Copeland, Occ. Pap. B.P. Bishop Mus. 
14(5): 52,1938. 
Forming tangled masses on dry hillsides. 
Widely distributed in the tropics and subtropics 
of the Old World with many recognized vari- 
eties in S.E. Asia. It is probable that there are 
also several varieties in the Pacific area, but 
these have not been worked out. 
Lintott 163, 164 (C), Twyford S.P. 135 (S), 
Williams 3038, 3081 (W), Fosberg 11221 
(K), Quayle No. X (K). 
HYMENOPHYLLACEAE 
Trichomanes endlicherianum Pr. 
Damp rocky faces in shady stream bed. This 
is the only record of a member of this family 
from Pitcairn, and as it appears to be fairly un- 
common, it has presumably been overlooked by 
previous collectors. The specimens are some- 
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