May 25, 1914 
Eremocitrus 
93 
the thermometer registered as low as 7 0 F. at 3 o’clock in the morning 
and at sunrise 14 0 F. This was at a point 70 miles north-northwest from 
the region where the desert kumquat was originally found, but at 1,800 
feet altitude instead of 1,300. On July 12, at his camp No. 48, at a point 
about 100 miles northwest of the locality where Eremocitrus glauca 
was discovered, Mitchell states that the temperature at sunrise was 11 0 F. 
This was latitude 24' 50" S. 
On June 3 while in the vicinity of Kings Ferry, 1 some 15 miles south of 
camp No. 32, the type locality of the species, the temperature registered 
16° F. at sunrise, which would indicate a 
possible minimum temperature of about 8° 
to io° F., if the same values hold here as 
at camp No. 41. This was at an altitude of 
1,400feet, nearly the same as at camp No. 32. 
It would not be surprising, in view of 
these scanty records taken at random, if 
temperatures as low as 5 0 F., or even zero 
Fahrenheit, would be found to occur occa¬ 
sionally in the region where the desert kum¬ 
quat grows wild. Such low temperatures 
might injure the leaves and perhaps the 
smaller twigs, but recovery would probably 
be rapid and complete. Certainly no other 
edible citrous fruit is native to any re¬ 
gion where it is exposed to such severe cold 
weather. 
DROUTH-RESISTANT ADAPTATIONS OF 
THE DESERT KUMQUAT 
Fig. 5. —Eremocitrus glauca; Cross sec¬ 
tion of leaf from near Forestvale, 
Queensland, collected by T. L. 
Mitchell on October 17,1846; in Gray 
The very first glance at a specimen of 
Eremocitrus glauca shows that it is a pro¬ 
nounced desert plant. Any one accustomed 
to seeing desert plants will be struck by 
the familiar gray-green color of the scanty 
foliage of small, thick, leathery leaves. So 
marked is the xerophytic character of the 
Australian desert kumquat that an experienced botanist on first seeing 
it exclaimed, “It must be some kind of sagebrush!” 
The cuticle is very thick, and the breathing pores are sunk below the 
surface and have very small air spaces below them. The leaves differ 
markedly from those of the ordinary citrous fruits in being provided 
with stomates and palisade tissue on both faces (fig. 5), making the upper 
Herbarium. Shows four ventral and 
two dorsal strata of palisade cells, 
central thin-walled cells often con¬ 
taining crystals of calcium oxalate. 
The outer wall of the epidermis is 
very thick. A stomate and an ap- 
pressed hair are shown on the upper 
surface; these organs occur also on 
the lower surface. X240. Drawn 
by Theodor Holm. 
1 This was near the present town of Donnybrook in Dublin County, Maranoa District. 
41217 0 —14-2 
