Lithops - Au Cactus Francophone

Hierdie twee portrette (Fig. 117–118) toon die geaardheid van die
woonpiek van die plant in die Ceres Karroo. Die plante groei in kleine holtes,
wat deur die verwering van die kalkklip ontstaan het. As dit reën, versamel
daar water in hierdie klein holtes. Fig. 119–120 dui wat die graad van variasie
van die boonste vlak is.
Henrici gives the following interesting description about the transpira
tion of Lithops salicola: “Lithops salicola, on the other hand, showed, as was
expected, a very low daily rate of transpiration which, however, did not
consist of a number of very small values, but apparently of a large number
of ‘nil’ values with an occasional good transpiration value.”
“Lithops salicola needs special mention. In 1938 the plant was fully
saturated (see Table 5). In this ease, too, the transpiration was munch higher
than during the drought of 1937, did not consist of a number of small val
ues, but of three large ones, two of them having been obtained during two
suc cessive hours showed nil values.”
“The succulent Mesembryanthemum floribundum and Lithops salicola
show the smallest hourly average, the smallest hourly maximum and smallest
daily value. . .”
“Compressing Table 1 and recalculating in minutes, the following av
erage values for transpiration per gram of fresh matter per minute would
be arrived at (only values up to 1937 are included).
Mesembryanthemum floribundum .5 to 1.5 mg.
Lithops salicola .002 mg.
Henrici gives the following figures
Transpiration rate of Lithops salicola per 1 gm. fresh matter
11/8/37 .00 .02 .02
2/3/38 .04 .40 .59
M. Henrici: “The Transpiration Rate of different Plant Associations
in South Africa” (1940). Dept. of Agric. and Forestry (Plant Industry Series
No. 39). Science Bulletin 185, pp. 17–18 and p. 27.
163