Horrowav.—Studies in the New Zealand Hymenophyllaceae. 609 
but they do not here adopt so characteristically the mat growth-form. On 
and of H. flabellatum are 
o m : 
must be noted also that as a high epiphyte H. multifidum, although much 
stunted, does not adopt the peculiar “mountain form," this being only 
LI LI . ta . n. f 
Above the forest-line, and in exposed subalpine localities generally, 
H. villosum and H. multifidum adopt the close mat growth-form. Of these 
quently a low epiphyte, being then an open creeper in the moss. Possibly 
i is th ас : s $ 
it 1s 
er, the underlying stratum of interwoven rhizomes an 
accumulated humus of the dead fronds and of the moss, is able to hold water 
over considerable periods of drought. 
D. The Bearing of the Distribution of the Species upon the Subject of the 
hylogeny of the Family. 
In the foregoing pages both the vertical and the altitudinal distribution 
of the various species has been considered. These facts will now be 
collected and their general bearing upon the subject of the phylogeny of 
the family discussed. The altitudinal distribution of the family has been 
summarized in Table C, on page 603. 
Table D, on page 610, sets forth in diagram form the vertical distribu- 
tion of the members of the New Zealand family as it is to be seen in 
Westland, the three species which do not occur there being also included 
for reference, their names being placed in parentheses. As the station in 
the forest adopted by a species varies very often with the particular locality, 
and is especially affected by the altitude, this table must be regarded 
as indicating the full vertical range of which each species is capable in 
Westland. 
From this table the following generalizations can be made :— 
1. The species whose fronds apparently cannot vary from the erect 
deltoid regular form of growth—viz., T. strictum, Т. elongatum, Н. demissum, 
. bivalve—are either altogether restricted to the forest-floor or have 
only to a very restricted extent acquired the epiphytic habit. Й: austr 
and the allied H. atrovirens illustrate the beginning of the modification 
of the typical terrestrial form of frond along with the adoption of the 
epiphytic habit. 
20—Trans. 
