226 JOUENAL OF THE EOYAL HORTICULTURAL SOCIETY. 
In its distribution it occurs in almost every part of the world. In 
England it is only known as a stove and greenhouse pest, but in 
Southern Europe it is commonly met with outdoors, and is generally 
looked upon as a pest wherever it occurs. 
In this country it infests Oleander, Palm, Agave, Erica, Passiflora, 
Dracaena, Azalea, &c. 
Several other species of Aspidioti occur in the British Isles, but they 
are much more sparingly met with, and without entering into micro- 
scopical details it would be impossible to differentiate their specific 
characters from those already given. I may add for your interest that 
the very destructive "San Jose Scale " {Aspidiotus perniciosus, Comstock) 
(fig. 96), of which we heard so much in the years 1898-9, is closely allied, 
and bears a close superficial resemblance, to A. ostreceformis, as will be 
seen from the illustration. But it has not so far made its appearance in 
this country. 
Pine -APPLE Scale 
{Dias2)is bromelic?, Kerner). 
The covering scale of this species is scarcely distinguishable from that 
of the common white " Eose Scale." It is, however, generally more or 
less circular, thin, almost flat, and pure white. Like other diaspids it has 
the power of burrowing beneath the epidermal layer of the plants, and 
when this happens the scale becomes almost hidden beneath the cha- 
racteristic covering of the Pine-apple leaves. 
The colour of the female varies from pale to bright yellow. That of 
the male is bright orange or orange-yellow, with the eyes and ocelli 
black. 
Curtis first called attention to this insect in the Gardeners' Chronicle 
for 1841, and says he found it in considerable numbers. I have only once 
received it from cultivated Pine-apples in this country, but have repeatedly 
seen it on imported fruit, and have succeeded in rearing the pretty little 
males from such consignments. 
This species has the habit of fixing itself near the base of the leaf- 
stalk, where it is difficult to get at without slight injury to the plant. 
When plants become badly infested the insects occur on all parts of them ; 
even the fruit does not escape. 
It is said to be generally common in other parts of Europe where the 
Pine-apple (Ananassa sativa) is cultivated. It has also been met with in 
the United States, and it probably occurs over a much wider area, as, 
owing to our speedy means of importing plants and fruits, such insects 
find their way into many new abodes. 
Boisduval's Scale 
{Diaspis Boisdtivalii, Signoret). (Fig. 97.) 
Without entering into very lengthy microscopic detail it is well-nigh 
impossible from superficial characters to determine this species from any 
other scale-bearing coccid. But some of my readers may recognise this 
greenhouse pest from the photograph. (Fig. 97.) The scale of the 
female is approximately circular, except when overcrowding takes place ; 
