118 
The Souih Australian Naturalist. 
but the greater part is held together by various plants. Where 
man or animals have not broken the surface, these plants hold 
the sand from drifting and fairly cover its surface Avith a mat of 
vegetation. The plants we see fall generally into one of two 
classes; ('ither they are greyish in color like the spinifex and 
saltbush, or they are a dark green with hard shiny leaves like 
the beri'y-bushes (Alyxia). The greyivsh plants are protected 
by a natural blanket of hairs as you see by examining them. 
The dark green leaves have a Avaxy covering as a protection. 
One of the commonest plants we notice is 
the Spinifex (Spinifex hirsutus). Its long, reed- 
like stems trail oAmr the sand in all directions, 
some of them reaching a length of many yards, and giving out 
at every joint bunches of leaA^es, Aidiich push their Avay up 
through the sand and serve to hold it from bloAving. The 
leaves are of the same silvery gray-green tint as those of the 
sialtbush. If we examine them closely we see this appearance 
arises from a coating of hairs, which protect the soft material 
of the leaves from the abrading sand. Follow 
up a stem, and you find bnuches of tiny 
rootlets at every joint, ramifying in all direc- 
tions and forming a very effectual liold for tlie sand against 
the moving poAver of the wind. The delicate groAving tip of 
the plant is very closely covered with stiff leaves armoured 
with a coating of hairs. AYith its abundance of rootlets pene- 
trating in all directions, the plant is able to secure the last 
drop of moisture held between the sand grains. The hairs, 
too, are so disposed as to protect and shelter the tiny breathing 
pores in the leaves, these being further sheltered by being at 
the base of little pits in the leaves. Like most successful plants, 
it sets plenty of seeds, and proAudes for their distribution over a 
large area. The fruits form a stiff ball Avhich, Avhen ripe, falls 
from the plant and is bloAvn by the Avind for long distances, 
until caught in some hollow of the sand, Avhere it comes to rest 
and is covered with bloAvn sand. A shower aauII start it into 
vigorous growth, and the sand meets a cheek to its drifting. 
But for these sand-loving plants the sandhills Avould con- 
tinue to drift and bring the barrenness of desolation oyer the 
fertile lands farther back. Man has often, by destroying the 
natural covering of the sand, started the sandhills moving, in 
many places with disastrous effect. Next to man come the 
animals he introduces, the sheep, cattle, and rabbits together 
rapidly destroying the natural cover. This has happened in 
our ’ own JState, particularly near the Coorong. 
Here aun in many other places man is ■ try- 
ing to replace the plants to hold the sand from spreading. 
Marram grass is one of the plants relied upon to establish itself 
