Lithops - Au Cactus Francophone

soil level and are then more easily seen. In the dry state the novice may walk
over them without seeing them. Sometimes they are found embedded in fine
limestone or amongst fine quartz pebbles and then they are not easily found.
I once made a photograph of L. gracilidelineata near Pforte, South West Af
rica, with a very good and large camera. The plant was growing among quartz
pebbles and in the field of vision was a chameleon. This chameleon was used
as a kind of landmark and yet when the negative was developed (Fig. 8) I
have failed to find the plant, although the print has been examined times
without number.
The author has seen a considerable number of Lithops in the field
and very rarely has one been seen that has been eaten by animals or even
shows traces of having been nibbled at. The mimicry protagonists will main
tain that that just proves their case, but one fails to see against what ani
mals these plants protect themselves. Protection against undue transpiration
is most likely the reason for the sinking of the bodies of these plants into
the soil. In any case these plants occur very often singly and would not form
adequate nourishment for any animal, how ever small. Frequently one finds
Lithops species hidden under bushes or aloes (L. Bromf ieldii). L. Lesliei, on
the other hand, grows in grassy places and in the summer and in winter is
often entirely covered by grass to such an extent that the clump is not visible.
The same applies to L. Aucampiae. Marloth in his “Stone Plants” refers to
Didymaotus lapidiformis as being a good example of the extent to which these
plants resemble their surroundings. My own experience is that once one has
seen a specimen of Didymaotus in the field, it can be recognised at a distance
of 16 yards, and that is a fairly big distance when it is remembered that the
plant itself is only about an inch or two in diameter and not more than half
an inch in height above the soil level. Even Lithops species are not always
difficult to find as is sometimes stated. It all depends on the stage of growth
of the plant, whether rain has fallen recently or not and whether the observer
has a trained eye. In time of drought the upper surfaces of these plants are
level with the dry and dusty soil and frequently covered with a thin layer of
dust or very loose soil particles of the same colour as the plant, so that they
are then extremely difficult to find.
The question why these plants resemble their surroundings both in form
and in colour has not been answered, and it is extremely doubtful whether it
will ever be answered. It is, of course, quite easy, as has been done by some, to
mount the Pegasus of phantasy and then postulate invisible or mysterious rays
emanating from the soil and then influencing the plant to such an extent as
to resemble it, but then one would be saying farewell to science and entering
the domain of speculation not based on experiment. Why, for example L. Le‑
sliei is rust brown in the reddish soil from ironstone and L. gracilidelineata is
whitish amongst the white quartz pebbles is a problem which still baffles us.
As far as I am concerned, I prefer to say with du Bois Raymond “ignorabimus.”
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