THE 
QUEENSLAND PHILOSOPHICAL SOCIETY. 
(From the Queensland Daily Guardian, June 29, 1867.) 
At a meeting of the Philosophical Society, 
held on Friday, June 28ib, the Kev. J. Bliss 
in the chair, the following paper was read by 
Dr. Bancroft : — 
Everybody has heard of sheep scab, many 
think it is a disease, some are aware that a 
minute insect is the cause of the mischief, but 
very few who have the management of sheep 
are able to recognise the parasite, or to eradi- 
cate it. Hence the law of this country com- 
pels the squatter to destroy his scabby flocks. 
To understand the nature of sheep-scab is 
very easy, and to remove it is by no means 
difficult. 
It is my intention to describe the sheep- 
scab insect, to show you specimens, and to 
point out measures to ensure its destruction. 
Scab, or hardened secretions that mat 
together the wool, may be the result of various 
diseased conditions, but the contagious scab 
here referred to, is that produced by the irrita- 
tion of a minute insect which bites the skin, 
causing it to discharge fluids that dry in the 
wool, forming hard brown encrustations, so 
extensive that the greater part of the fleece is 
often matted together by them. 
The sheep suffer much from itching of the 
skin, which causes them to pluck wool from 
the parts they can reach ; they also rub a great 
deal off other parts, so that they have no fleece 
of any value. Their health also suffers from 
the continuous irritation, which is most intense 
in warm weather. Purulent secretions, from 
ulcers and boils, are poured out, and fissures 
among the scabs bleed when the animal rubs 
itself. Emaciation commonly takes place. 
The scabs can be softened by water, and with 
great pains removed from the wool. 
They consist of hardened serum of the 
blood, pus, blood, epidemic — scales, and 
foreign matters mixed therewith. It is often 
thought advisable to remove these scabs in the 
treatment of the disorder, but there is no 
necessity to do so. 
The scab described is simply the result of 
the irritation produced by a parasite of the 
arachnida or spider family. 
Ir is a mite of about a thirtieth of an inch 
in diameter, and can be seen by the naked eye, 
as a minute white speck, firm and globular, not 
a mere scale, such as may anywhere be lifted 
from the skin. 
When a person with good eyes has had 
the insect shown to him, he will be able to 
pick them from among the fibres of wool with 
great ease. By putting an insect between two 
pieces of window glass, and using slight 
pressure, its legs may be seen. A drop of oil 
will better enable one to see the parts of its 
body, and a weak lens will magnify it suffi- 
ciently for ordinary examination. An insect 
so imprisoned in a drop of oil and held up to 
the light of the sun or a candle, cannot be mis- 
taken for anything else, and its movements, if 
not too tightly pressed, can be well observed. 
Should it be difficult to find the insects on 
the living sheep, the skin of a newly-killed 
animal will be more convenient for examina- 
tion. 
The insects will be found at the bottom of 
the fibres of wool, not far from the scabs. 
They do not live on the scabs, for having set 
up irritation, causing scabs to form in one part, 
they move to sounder skin. 
They will often be found on the fibres of 
wool along which they have the power to climb 
— also adhering to the skin, though, unlike the 
itch insect, never burrow under it. With 
careful search, a family party of twenty or more 
may be found together, the individuals of which 
