616 Transactions. 
Lycopodium and the Astelias are also well adapted for their station. The 
delicate nature of the frond-lamina of the high epiphytic Hymenophyllaceae, 
and the complete absence of any water-storing tissue, frond-tomentum, or 
cuticle, is in striking contrast to the structural modifications in the other 
high epiphytes. 
As a result of his investigations into the physiology of the Jamaican 
ymenophyllaceae, Forrest Shreve concludes (26, p. 208) that the xerophily 
of the epiphytic species “resides not at all in their structure, but in the 
capacity of the protoplasmic utricle to withstand the removal of the sap 
which is its source of water and nutrient salts." The facts with regard 
to the New Zealand epiphytic species go to show that this statement must 
be somewhat modified and amplified before it can be applied to the family 
as a whole. The frond of Н. Malingii shows a truly remarkable structural 
modification, even although this species occupies only a mid-epiphytie 
station. It is possible that the multi-layered condition of the fronds of 
H. dilatatum, H. scabrum, and T. reniforme is to be regarded as a recent 
modification rather than as a primitive feature. But a most important 
and effective modification in accordance with the epiphytic station is that 
which takes place in the growth-form, and it is probable that further 
study of the family will show that elsewhere also this is partly responsible 
for the wide vertical and altitudinal range of this hygrophilous family. 
GENERAL CONCLUSIONS. 
Westland a certain proportion of the species belong altogether 
e t 8, 
4. Those species which have the widest vertical range in the lowlands 
of Westland are, with the exception of H. Ma Api, those also which 
have, both in Westland and in other parts of New Zealand, the widest 
altitudinal range. : 
