1 Juxr, 1898.] QUEENSLAND AGRICULTURAL JOURNAL. 507 
from its presence. The outlay that the adoption of this treatment necessitates 
is, however, sufficiently great to forbid its employment except when the 
appliances are owned and utilised by individuals, companies, or societies that 
make it their special business to conduct such operations at a stipulated cost 
per tree, as is already done in California; or when there is a co-operation in the 
work between Government and grower, resulting in the supply of labour by 
the latter, and of outfit, chemicals, and skilled supervision by the former.* 
In conclusion, should any of the readers of this article discover upon their 
trees any scale insect that they may either infer to be San José Scale from the 
foregoing description, or regarding the nature of which they, notwithstanding 
it, have doubt, it will be in their interest to forward portions of the wood 
whose condition has claimed their attention, or aroused their suspicion, to this 
office—that their true state may be ascertained, and that—should the 
pernicious insect be present—they may be furnished with the latest information 
to hand with regard to the best means for its‘extermination. 
PERNICIOUS SCALE ON EUCALYPTUS 
Supplementary Note. 
In 1895 the late W. M. Maskell announced (Trans. New Zeal. Inst., vol, xxiii., p. 386) the 
receipt, from G. Quinn, of Adelaide, of twigs of Zucalyptus corynocalyx ae covered with 
scale insects that he concluded were identical with Aspidiotus perniciosus. ‘‘'The puparia (he 
writes) in this instance are very dark-grey, and the larval pellicle is orange-red. ‘Ihe second 
pellicle is not visible until the scale is turned over, and then only indistinctly. But the characters 
of the adult female are quite clearly those of A. perniciosus. I have also the advantage of finding 
some adult males which are identical with the figure of A. perniciosus, given in ‘ Insect Life’ (vol. 
vi., p. 367).? a 
Two thee after this C. Fuller (‘Notes on Coccidee—I., Some Coccide of Western Australia,” 
p. 4, Perth, 1897) recorded the occurrence in Western Australia of a scale insect on Tasmanian 
gum (HZ, globulus) that he regarded as being a variety of Aspidiotus perniciosus, but a distinct 
insect. ‘This he named ‘‘eucalypti.” In his description he gives the colour of the scale proper 
as ‘‘ purple black,” but, however, does not point out in what features the distinctive characters of 
the variety reside. - > ‘ 
Finally, during the present year, C. French has stated (“The San José Scale, 1898,” p. 8) “the 
fact of a variety of San José Scale, named cucalypti, being very plentiful on bark of gum-trees in 
parts of the Wangaratta district” of Victoria. The appellative ‘“‘eucalypti” is, moreover, attributed 
by him to Maskell (French in Jit.) } . hate p 
Assuming that the scale insects mentioned as occurring upon Eucalypt, in Victoria, South 
Australia, and Western Australia, respectively, represent a single species (although even with 
regard to this there is doubt), it is therefore uncertain whether this be identical with the San 
José Scale, or different from it—as C. Fuller’s and C. French’s statements seem to imply. This 
is a matter of importance, since if they are identical the work of coping with the Pernicious or 
San José Scale will be complicated by reason of its infesting native trees in addition to those of 
our orchards ; but if different this difficulty will not have to be enconntered. 
_ With regard to South Australia, the United States authority on Scale Insects, TI’. D. A. 
Cockerell, has stated (‘‘The San José Scale and its Nearest Allies,” p. 15) that he is “quite 
convinced that the supposed variety of perniciosus recorded by Maskell as on Eucalyptus 
in Australia is not that insect; the description reads more like A. forbes?, but it is very likely 
something else.” Mae r 
Again, from an examination of specimens of the Wangaratta insect, obligingly communicated 
by the Government Entomologist of Victoria, the present writer has no hesitation in pronouncing 
them as quite distinct ; as is very evident when regard is had to minute structural features. Thus 
in typical examples of A. perniciosus it will be found, on examining the terminal segment of the 
body, that the marginal plates or ‘squames” are narrow and very feebly serrate on their anterior 
sides, whereas in eucalypti they are conspicuously branched or fimbriate in this position, as in 
A. howardi, Cockl. Moreover, in the latter insect, the lateral lobes are narrower, and though 
obtuse somewhat obliquely truncated, with the emargination apparently obsolete. These characters 
co-exist, in the specimens under examination, witha special colouration of the scale. This is pale 
testaceous brown, without any trace of black or grey, with the exuviz (pellicles) orange-yellow, 
especially when viewed from beneath. This colouration is also participated in by the scales when 
still immature. (However, the examples are dry and long gathered.) _ ’ jf 
C. French writes (J.¢.):—‘‘ It is not known as yet whether this variety will attack fruit trees 
or not.” The outcome of the present examination would lead one to suppose that the latter 
event will not be found to transpire. 
*The fumigation of trees for the extermination of scale insects as a procedure in orchard 
work has already passed far beyond the experimental stage, and is already extensively resorted to 
in some countries. The description of the process as conducted, as well as of the appliances used, 
must, however, form the subject of a special article. : 
