196 The Biology of the Higb Mountain Plants. 
great peltate leaves of Ranunculus Lyallii are often filled with water after 
rain, but whether such is absorbed to any extent is not known. Ecologically 
they function in strongly shading the partially buried rhizomes and in preventing 
occupation of the ground by other plants. Filiform leaves with rolled margins 
are characteristic of the steppe grasses.  Amongst the more remarkable are 
. Poa acicularifolia and P. pygmaea, both cushion or semi-cushion plants, those. 
of the former more or less than ı5 cm in diam. and those of the. latter 
5—ıo cm. The leaves of the 2. acicularıfolia are about 8 mm long, strongly 
involute, stiff, curved, smooth and terminating in: a sharp point; those of 
. pygmaea are rigid, coriaceous, folded and frequentiy not more than 4 mm 
dng. Another remarkable grass is Danthonia pungens of Stewart Island. This 
lains large patches of tufted culms from a woody root-stock bearing the 
somewhat distant sub-imbricating leaves which are not erect but stand out 
obliquely; they vary in length from more than 30 cm to 5 cm or even less 
and are extremely stiff and coriaceous, thick, pale-green marked with. brown 
and taper gradually to a sharp truly pungent apex; the blade is equitant, 
_striated and waxy on the upper surface; the leaf-sheaths are long, about g mm 
broad at the base in large examples and they persist attached to the plain 
" slowly rotting, and holding much moisture: 
The roots of the class of plants under consideration are, in no a degree, 
in harmony with the station. Thus extremely long roots are more common 
in plants of rock, stony debris, steppe and fell-field than elsewhere. In some 
cases, roots do not descend deeply but spread laterally, at times, more or less 
parallel with the surface. The length of roots of different species growing side 
by side appear to differ considerably, but I have not sufficient observations 
to go i into this er. matter in detail. : 
ER 
2. Pollination. Ge ni 
As ARE wie book the matter of pollination can receive only the 
most superficial treatment.  Though butterflies are scarce in the mountains, as 
where, there are abundance of Diptera, moths and beetles, so that there 
' no lack of insects for pollination purposes. Furthermore, the frequent hig 
winds must carry the pollen long distances. The alpine plants, in general, [ 
abundance of seed. It is trı are n 
er he 597 ats en species a 
aside the 118 ferns, Giperaceae and Gramineae &c., the total to be dealt 
of which the flowers. of 62 pP c may be considered | monocl 
