304 THE -MEDITERRANEAN NATURALIST 
carbonic dioxide, and then percolating through, the 
limestone, it dissolves and carries away in solu- 
tion the carbonate of lime of which it is largely 
composed. Evaporation follows, and by means of 
another chemical change this lime is again depu- 
ted as an insoluble substance, known to chemists 
as bi-ca.-bonate of lime. 
In this way vast caverns are formed in the very 
bowels of the earth, and many of them are 
draped and festooned in a most fantastic manner, 
with stalactites and stalagmites that have been de- 
posited after the evaporation of the water, which 
has done the work of excavation. 
The “Ta Ninu” cavern on the “Ta Xaghra” hill at 
Gozc* and the stalagmitio cavern, popularly known 
as “Calypso’s Grotto,” in which the lovestricken 
goddess is said to have held her court, and to have 
entertained Telemachus after his shipwreck, may 
be cited as examples of the magnitude of the work 
effected through the instrumentality of objects 
apparently so trivial and insignificant. 
But let us descend the terraced sides of the val- 
ley, passing cn route tli e gnarled and. twisted trunks 
of numerous carob trees, pomegranates, German 
medlars, wild plum trees, orange trees, silken-rye 
grass, and the host of other trees and plants with 
which the well-tilled slopes of this fertile spot 
abounds, and wend our way onward to the little 
springs whose rippling music had attracted our 
attention when standing on the heights above. 
What a blending of rural rusticity and wild rug- 
ged grandeur do we not here find? Immediately 
around us, the springs ripple and dance onwards 
amid a wealth of verdant watercresses apcl sweetly- 
scented wild flowers; while in the background 
loom up dark and gray the craggy heights of the 
Binjemmap the brilliantly white limestones and 
the rich warm colouring of the marl-beds of which 
lend an effect of beautiful and substantial magnifi- 
cence to the scenery. 
But do our charges against the plant world of the 
islands rest here? Assuredly not. Let us examine the 
banks of the streamlets whose water are eddying 
onwards through their marly channels, and we shall 
find numerous fresh instances wherewith to impli- 
cate them. Several of the trees that are growing on 
the banks have been so vigorous in their exertions 
to drive their roots in the direction of the water 
that they have undermined a neighbouring wall, 
and have caused their root.- to appear in the very 
bed of the brook. This action has loosened the 
soil in the vicinity, and while in that state, e n.-i- 
! derable quantities have been carried onward by the 
current and washed into the sea. 
This is example, on a small scale, of wL at is hap- 
pening to the banks of rivers in other countries, 
on a scale of, considerable magnitude. 
The undermining action of the waters is f; . Sta- 
ted by the preparation made for it by the r< ns of 
the trees that grow on the banks: and when as 
often occurs, the trees themselves are precipitated 
into the flood, either by the force of the gale or by 
being themselves undermined, they cany with 
them tons of soil, and thus open up inequalities, 
that can only be effaced by a considerable l iteral 
extension of the stream itself. 
A walk in any direction alone the southern coast 
of the islands will furnish us with endless exam- 
ples of the various ways in which "plant life" assist? 
in degrading rock surfaces when the conditions are 
favourable. The southern slopes are strewn with 
boulders that have broken off from the Upper 
Limestone, and have rolled 3 hillsides, thus 
suggesting, from their great numbi rs and huge 
proportions, the idea of a vast labyrinth of Cyclop -e- 
ian anarchy. 
And yet nothing more terrible has caused this 
destruction than the ceaseless attacks of those 
atmospheric agencies, which bv eroding tin subja- 
cent Sand and Marl beds, have caused the super- 
incumbent limestone to break off and precipitate 
itself down the slopes. 
Though this work is largely due to the combined 
action of a variety of aerial agencies, yet even here 
the humus of decaying vegetable matter plays its 
part and adds its quota in assisting in the work 
of devastation. 
The weatherworn and fretted appearance which 
is the chief characteristic of the surface, of the 
south eastern portions of both islands may in like 
manner be attributed to these causes. 
These extravasations on the rock surface are the 
means whereby, in winter time, a certain charm is 
imparted to these otherwise rugged and sterile 
portions of the islands, for the potholes then serve 
as so many natural flowers piots in which luxuria- 
tes a Wealth of verdure; but this state of things 
endures only for a few months, for when summer 
