30 
baps be impossible at this late day to definitely settle the question of this 
original source, especially as there may have been not one bnt several in- 
troductions (indeed we have evidence that such was the case) into all 
three of the countries in which it now occurs; but we can much easier 
understand its travels if it started as a sugar-cane insect. I have itali- 
cized those parts of the following letters which particularly bear on the 
subject of this communication. 
The sketch of the Dipteron, which Mr. Crawford found attacking 
Icerya, shows a great likeness in the body to some hymenopterous En- 
cyrtids ; but the wings indicate its Dipterous character and that it be- 
longs to the Dolichopodid;e near Diaphorus. So far as their larval 
habits are known, these flies are predaceous and live in the larva state 
in the ground. Perhaps Mr. Crawford has used the term "parasitic" 
synonymically with u predaceous," but I will not further anticipate what 
Miss Ormerod may report.* 
EXTRACTS FROM CORRESPONDENCE. 
[The following are the extracts from the correspondence to which ref- 
erence is made above. — Editors Press.] 
Letter from Roland Trimen, of Cape Town, to Professor Riley. 
As regards the evidence as to the Australian habitat originally of this insect, I re- 
gret that I have nothing to add to what has been already supplied to you. 
* T? IT * Tf * * 
Since the commissioners report in 1877, the orauge industry of the western dis- 
tricts has suffered most severely, scarce, very inferior, aud exceedingly dear fruit be- 
ing now only obtainable where it used to be abundant, good, aud cheap. Where, 
however, the kerosene aud alkaline solutions have been constantly applied by indi- 
vidual proprietors here and there, the result (as I am informed by Mr. MacOwan, di- 
rector of the botanical gardens) has been very encouraging. In the eastern districts 
the effects of the Icerya's attacks do not seem to have been nearly so serious, but 
whether this is due to a less suitable climate and other conditions, or to more vigi- 
lance and exertion on the part of cultivators, I cannot at present determine. 
* Since this was written I have received two specimens of the insect itself through 
the courtesy of Miss Ormerod. These specimens are so much m utilated that it is al- 
most impossible to accurately place them. The enlarged ligure seut by Mr. Craw- 
ford was very misleading, the venation of the wing being wrong and also the an- 
tenna?. It has no second cross vein on the wings and no sort of resemblance to the 
actual anteuiue, while the two basal cells on the wings arc lacking. It Isquitelikely 
that this fly belongs to a new genus. The specimens were sent to Dr. S. W. Willis- 
ton, who reports that lie considers them Oscinids, but that further than t hat he could 
venture no opinion as he can locate them in no genus with certainty. 
Iu reference to natural enemies of the Icerya, it is of interest to note that a liitle 
lady-bird. Rodolia icerya}, of which Miss Ormerod has sent me a figure, has been found 
to do good work and to destroy the pesl in Australia, while news comes from Cali- 
fornia that Chilocor us cacti is doing such excellent work that the trees iu some local- 
ities are being entirely Greed through its instrumentality aud the lady-birds are act- 
ually being sold to orange-growers at so much per ounce. C, V. R. 
