Chromosome Numbers in Some Pacific Pteridophyta 
G. Brownlie 1 
ABSTRACT: Haploid chromosome complements are recorded for two species of 
Psilotaceae, and for 36 species and one variety of ferns (27 species from New 
Caledonia, 7 species and 1 variety from New Zealand, and 1 species from New 
Guinea ) . 
It is suggested that Schizaea fistulosa LabiiL and Schizaea fistulosa var. australis 
Gaud, are specifically distinct. A further 
varied species of Lindsaea together with 
may constitute a distinct fern family. 
The value of cytological records of the 
type listed below lies in the contributions they 
can make to an understanding of relationships 
within groups of plants. Information such as 
this complements earlier morphological work, 
and can be used only in conjunction with such 
records, for it is in itself merely another morph- 
ological criterion. It can either support previ- 
ously held views or point the way to more 
detailed research and possible re-examination 
of certain accepted relationships. 
The majority of chromosome numbers listed 
here are from New Caledonian species of ferns, 
this island having been selected because of the 
great interest that its flora arouses in relation 
to phytogeography and plant relationships in 
the Pacific. This island possesses in its fern 
flora species and genera which are less closely 
allied to recent Malaysian forms than those in 
the bulk of Pacific island floras. In this respect 
is it similar to New Zealand. 
Reasonable samplings of chromosome num- 
bers in ferns have already been done in Ceylon 
(Manton & Sledge, 1954), Malaya (Manton, 
1954), New Zealand (Brownlie, 1954, 1957, 
1958, 1961), and in India by Mehra and his 
associates (Mehra, 1961). These samplings 
come from the two extremities of the arc from 
continental Asia to New Zealand, so that any 
records from the area between are of particular 
interest. 
1 Department of Botany, University of Canterbury, 
Christchurch, New Zealand. Manuscript received De- 
cember 19, 1963. 
suggestion is made that the cytologically 
such genera as Loxsoma and Leptolepia 
NOTES ON CRITICAL GENERA 
Schizaea 
Records of chromosome counts in this genus 
are few (Lovis, 1958; Brownlie, 1961) but 
these bear out the generally held belief that 
the present species are relics only of an old 
flora. The present two counts would indicate 
that Schizaea fistulosa Labill and Schizaea aus- 
tralis Gaud, should be regarded as two distinct 
species, the latter confined to mountain and 
southern areas of New Zealand, the former hav- 
ing a much wider range. 
Lindsaea 
Several species of this genus from Ceylon 
and Malaya have been recorded by Manton, 
mostly with a base number of n = 50, but the 
impression that it is probably an unnatural as- 
semblage is suggesed by the numbers of n = 
c.40 and c.47 for two species listed here and 
of n = 34 and c.42 for two other species (L. 
linearis Sw. and L. trich omanoides Dry.) from 
New Zealand. It is possible that here we have 
two morphologically parallel groups represent- 
ing two geologically widely-spaced periods of 
development, those of the n= 50 group being 
a recently diversified section comparable with 
such modern families as the Aspleniaceae and 
the Polypodiaceae, and the other section being 
remnants of a much older flora. Several species 
of this older group occur in New Caledonia, 
but cytological information on these is still lack- 
ing. Manton (1958) has already indicated the 
complexity of Copeland’s Pteridaceae. 
493 
