95 
throughout the town. In the space of four years three-quarters of 
these trees have disappeared, their destruction having been brought 
about by the ravages of a species of mealy bug, Dactylopiie 
perniciosus. Such are the depredations of thes pest that in four 
months it will entirely destroy the largest tree. Although it is 
only of recent years that this mealy bug has made its presence 
felt it has doubtless existed in Egypt unnoticed for a number of 
years. 
The insects can be found on almost every Lebbek in the 
neighbourhood of Cairo but it is only in the town itself that it has 
caused serious damage. Here the trees planted in paved and tarred 
streets, deprived of air at the roots except that provided by a small 
grating, and shut in by high houses on each side, were growing 
under unnatural conditions and were in consequence in indifferent 
health. On the Gesirah side of the Nile, where the paths are not 
paved or the roads tarred, and where the trees are exposed to every 
wind, the mealy bug though everywhere present, makes no headway. 
It would seem therefore that the increase of the insect is influenced 
by the state of health of the host. The attack begins in May, is at 
its height in June and July, and commences . Sage pe in August. 
The species appears to be very prolific. C. Willcocks, 
entomologist tq the Khed divisl Mecety a Spee ont 
1100 eggs in the ovisac of a female. 
The young larvae settle on the twigs and in the axils of the leaves 
and the trees then appear to be covered with lumps of dirty white wool. 
Presently the whole crown of the tree shrivels, presenting a scorched 
and blackened appearance. The leaves then fall, but many are 
caught and retained by the sticky secretion of honey dew given off 
y the insects, and by their slightly adhesive ovisacs. Little 
Bailes of fallen leaves and stamens thus accumulate all over the 
tree, giving it a bunched appearance. These pees BY leaves 
orm a very efficient protection to the insect and render the 
application of spraying emulsions almost ones In ‘A ipiiet the 
tree is completely defoliated and in a few months it dies. As above 
mentioned, spraying unless carried out at an early stage, is of little 
avail, and furthermore the height of be trees renders the operations 
very difficult of thorough perform nee. A drastic remedy tried 
was that of cutting back the fees: attacked almost to the main 
trunk and cleansing with a strong petroleum emulsion applied with 
a stiff brush. 
The trees so treated, however, nearly always died, or if ee 
survived were permanently spoilt in appearance. There can be no 
doubt that the Lebbek is doomed as an avenue tree in Cairo, except 
under the most favourable oladscone The problem that re 
is to find the most suitable trees to take its place. The cane of 
relying on one species only has been sufficiently demonstrated. 
An interesting account of the mealy bug, illustrated by some 
ee photographs, both of the pest and the infected trees in 
iro, was published by Mr. F. C. Willcocks in the Bulletin of 
stexnchogica’ Research, Vol. I. pp. 121-141 (1910-11). : 
