( 3 ) 
In a letter received by me in March, 1887, Mr. Bairstow 
reports, “ The Australian Bug seems to be extending 
operations in Bloemfontein and higher up country ” : 
this observation shows a spread over a length of country 
of 680 miles (if we take the town of Bloemfontein for one 
extremity, and Cape Town, whence it was first reported, 
for the other) during the fourteen years which have 
passed since the first observation, thus showing an 
average rate of advance of little less than fifty miles 
a year; and a glance at a map of Southern Africa, 
showing the vast area of the eastern division which was 
infested by this pest as early as 1877, shows its powers 
of naturalisation, and breadth of country occupied. 
Where it came from does not appear to he proved, but 
the balance of opinion turns towards Australia. Prof. 
H. Comstock, the chief authority regarding this insect 
up to the present time,* * * § says, in his Report,! “ It seems 
probable that it is an Australian species,” and mentions 
that the first published notice of its appearance in the 
United States of America]; which he had been able to 
find was in 1877, by Dr. A. W. Saxe, of Santa Clara, 
who stated it as his belief that the pest was originally 
brought from Australia, on some plants imported by 
Mr. G. Gordon, of Menlo Park, in 1868, and that it 
spread all along the coast counties.” 
Prof. Comstock mentions that the specific name that 
has been adopted, namely, purchasi , was given this 
insect by Mr. Maskell, § and that “ it was found on a 
hedge of ‘ kangaroo Acacia ’ in Auckland, New Zealand, 
in great numbers, but upon that single hedge alone.” 
In the Report of 1877 by Prof. Trimen, quoted above, 
he mentions that the Director of the National Museum 
* When these lines were going to press I was favoured by receipt from 
Prof. Biley of his valuable and exhaustive paper on I. purchasi, giving 
full information of habits and remedies up to date, to which I refer in 
preface. 
f Keport of the Entomologist in Annual Eeport of the U. S. A. Depart¬ 
ment of Agriculture for 1880. Washington, 1881. 
I In the ‘ California Agriculturist and Artizan ’ for December, 1877. 
§ Trans, and Proc. New Zealand Inst., vol. xi., p. 221. 
4 
