Hotioway.—Studies in the New Zealand Hymenophyllaceae. 593 
on fallen logs, mossy boulders, &c. It occurs also at the bases of ya 
mountains, and more especially in the valleys and creek-beds up to a 
altitude of about 1,300-1,400 ft., ig it is here more locally “ae 
y 
, bei 
I have never observed the two species overlapping in тат distribution 
flank, the altitude at which the one is gives place to the other varies 
. Tunbridgense is extremely variable in ita odi form, but from the 
fact that the different forms are not found intermixed, and that they are 
characteristic of slightly different stations, it would seem that they are the 
expression of small differences in the environment. Four such forms com- 
monly to be seen in Westland are represented on Plate 68. That marked D 
shows the species in its normal state. А is a much larger-fronded form 
with large sori, occasionally to be met with on the under-side of fallen logs. 
B is an attenuated form which I have met with both on bare overhanging 
tree-trunks, where the fronds are freely pendulous, and also more especia 
in thick moss on the wet rocky walls of narrow ravines. In the latter 
station fronds were found up to 6 in. in length in which the lateral pinnae 
throughout the frond remained so completely undeveloped as practically to 
function only as short peduncles to the sori. It was shown above that 
H. ferrugineum also adopts the attenuated form when growing in moss on 
the dripping vertical rocky walls of narrow ravines. The smallest form, C, 
is that adopted by H. У тоу, commonly when growing at а 
an usu 
a whole much larger and heavier than in any of the Westland varieties 
noted above. The sorus is also here especially large. This variety is not 
illustrated at Plate 68. Of all these varieties the latter alone can possibly 
be taken as indicating that in this species there may be fixed geographical 
races, but the extraordinary variability of H. T'unbridgense suggests that it 
represents a stock from which other species have diverged. 
Н. peltatum occurs in two main forms according as the situation is 
secluded or exposed. bx narrow forest-sheltered gullies among the moun- 
tains this species may be found in thick wet moss on ме horizontal boughs 
of the Fuchsia and Olearia shrubs which so commonly occur in these water- 
courses. Here it grows most luxuriantly, the fronds Milano showing 
when pendulous two or even more fertile zones (see Plate 68). It also 
occurs at the same altitudes in larger open creek-beds in close mats on 
the boulders, the fronds here being stunted and curled with imbricating 
pinn This s ecies is never found in Westland on the actual flanks of 
the mountains, but is restricted to the more humid and sheltered gullies. 
The chief characters separating H. Tunbridgense from H. peltatum relate 
to the branching of the pinna, the disposition of the sori, and the nature 
