184 
PLINr'S NATUEAL HISTOET. 
[Book XIII. 
hundred stadia from the 'NUe, and watered by springs of its 
own. 
(10.) Here we find, too, the Egyptian plum-tree, not much 
unlike the thorn last mentioned, with a fruit similar to the 
medlar, and which ripens in the winter. This tree never loses 
its leaves. The seed in the fruit is of considerable size, but 
the flesh of it, by reason of its quality, and the great abund- 
ance in which it grows, affords quite a harvest to the inhabit- 
ants of those parts ; after cleaning it, they subject it to pressure, 
and then make it up into cakes for keeping. There was for- 
merly a woodland district in the vicinity of Memphis, with 
trees of such enormous size, that three men could not span 
one with their arms : one of these trees is remarkable, not for 
its fruit, or any particular use that it is, but for the singular 
phsenomenon that it presents. In appearance it strongly re- 
sembles a thorn,^'' and it has leaves which have all the appear- 
ance of wings, and which fall immediately the branch is 
touched by any one, and then immediately shoot again. 
CHAP. 20. (11.) NINE KINDS OF GUM. THE SAECOCOLLA. 
It is universally agreed, that the best gum is that produced 
from the Egyptian thorn ; it is of variegated appearance, of 
azure colour, clean, free from all admixture of bark, and 
adheres to the teeth ; the price at which it sells is three 
denarii per pound. That produced from the bitter almond- 
85 This is from Theophrastus, Hist. Plant. B. iv. c. 3. Fee suggests 
that it may have been a kind of myrobalanus. Sprengel identifies it with 
the Cordia sebestana of the botanists. 
85 <' Fuit.'* From the use of this^ord he seems uncertain as to its ex- 
istence in his time ; the account is copied from Theophrastus, Hist. Plant. 
B. iv. c. 3. Fee suggests that he may here allude to the Baobab, the 
Adansonia digitata, which grows in Senegal and Sennaar to an enormous 
size. Prosper Alpinus speaks of it as existing in Egypt. The Arabs call 
it El-omarah, and the fruit El-kongles. 
87 The Mimosa polyacanthe, probably. Fee says that the mimosas, re- 
spectively known as casta, pudibunda, viva, and sensitiva, with many of 
the inga, and other leguminous trees, are irritable in the highest degree. 
The tree here spoken of he considers to be one of the acacias. The pas- 
sage in Theophrastus speaks of the leaf as shrinking, and not falling, 
and then as simply reviving. 
^8 The Acacia Nilotica of Linnaeus, from which we derive the gum 
Arabic of commerce ; and of which a considerable portion is still derived 
from Egypt. 
