496 QUEENSLAND AGRICULTURAL JOURNAL. [1 Junz, 1898. 
In Queensland the’ Pernicious Secale has been observed infesting apple, 
- pear, quince, plum (Prunus domestica), Japanese plum, peach, nectarine, apricot. 
Tt would appear also that the Winter Majentin and Northern Spy variety of 
apples are not proof against its attacks, though with regard to the occurrence 
of Woolly Aphis they are usually regarded as being “ blight-proof.” 
INJURY, 
On the general subject of the damage effected by this insect, the following 
testimonies may be be cited:—Messrs. Chapin and Vestal, reporting to the 
Santa Clara (California) Horticultural Society in August, 1881 state that 
“it does not simply check the growth of the tree, but it covers it literally 
entirely, and the fruit nearly as much so, rendering it unsaleable and unfit for 
use, and if left the tree is killed in three years’ time.” (VIIL., p. 124.) 
“There is, perhaps, no insect capable of causing greater damage to fruit 
interests in the United States, or perhaps in the world, than the San José or 
Pernicious Scale. It is not striking in appearance, and might often remain 
unrecognised, or at least misunderstood; and yet so steadily and relentlessly 
does it spread over practically all deciduous fruit trees—trunk, limbs, and 
fruit—that it is only a question of two or three years before the death of the 
plant attacked is brought about, and the possibility of injury, which from 
experience with other scale enemies of other deciduous trees might be easily 
ignored, or thought insignificant, is soon startlingly demonstrated.’—L. O, 
Howard and C. L. Marlatt. (X., p. L.) 
So far as has up to the present been observed, the Pernicious Scale would 
appear to be as destructive in Australia as in the United States, to its occur- 
rence in which, these testimonies relate. y 
APPEARANCES OF INFESTED TREES. 
Full Infestation —Owing to their small size and their colour, that usually 
harmonises with that of the surface whereon they occur, individual examples 
of the insect will usually escape the notice of the untutored eye or average 
fruit-grower, especially if their occurrence is largely restricted to the older bark, 
as is generally the ease in the first instance, until it has already become very abun- 
dant. Then we find the bark unlike that of healthy trees, being finely, although 
unevenly roughened, dull, of adarkerhuethan usual, greyish-coloured,and covered 
with a more or less scurfy deposit; looking as if it had been coated with a mixture 
of lime and ashes or lime and soot, or dusted with a fine powder composed of 
these matters on a previously applied dressing of some sticky substance. These 
appearances are well shown in Plate XL, whereon photographs by I’. C. Wills, 
Artist to the Department, are reproduced. igs. 1 and 2 represent clean 
and scale-infested bark of the apple as seen without magnification. When 
infestation is at its height there will be no break in the continuity of these 
features, and numerous small fissures displaying the inner bark may already 
be noticeable, especially in the case of the pear. When this stage has not 
guite been attained, 1f it be a pear-iree that is being regarded, on close 
examination one will notice small darkish groups, running into one another of 
densely occurring, tiny, slightly raised blackish spots like grains of black 
pepper. In the case of the peach, the usually grey, fine, paint-like matter 
(well shown in Fig. 4, as it appears when magnified) on the surface of the 
bark will appear to have been everywhere split open to give presence to 
similar masses of particles. The above-mentioned encrusting matter may 
readily be scraped off with a knife or with the finger-nail, or even be removed 
by aid of a stiff brush, during which operation a yellow oily liquid will be 
noticeable formed by the crushed bodies of the insects that compose it. 
Viewed with a magnifying glass (a good “cotton tester’ will serve the 
purpose) prior to such removal, it will be seen that the entire surface, or 
thet whereon the above-mentioned little groups occur, is covered with minute, 
rounded or oval, flatly conical scales, the tips of which are crateriformly 
