234 Annual Report for 1907 of the Zoologist. 
They are Tyroglyphus siro and T. longior. A remarkable 
case was reported in September where the latter species was 
present in such enormous numbers round a clover stack as to 
attract the attention of the owner. They may always be found 
if searched for in such situations, but seldom occur in sufficient 
numbers to be noticeable. The circumstance is not unpre- 
cedented however, for Michael in his monograph mentions 
having seen a stack which appeared to consist quite as much of 
mites as of clover, and which was absolutely ruined by creatures 
so small as to be only just visible without a microscope. 
Treatment . — The circumstances under which these different 
pests may appear are so various that it is impossible to devise 
a remedy which will fit every case. They have one point in 
common, however, for the trouble nearly always begins through 
neglecting to remove waste material from granaries or store 
rooms. Waste corn or meal left lying about is a danger to the 
mill or granary, and in the same way moth or beetle-infested 
clothing or food in a house, unless speedily removed, may lead 
to the whole building becoming infested. The first care, then, 
is to search for and destroy the material which has given rise 
to the particular attack. Other measures will necessarily 
depend on the circumstances. 
For stored grain or any material which can be placed for 
treatment in a closed bin, carbon bisulphide is the most effective 
insecticide in the hands of one who can be trusted to use it 
with the necessary caution. It is placed in open vessels on the 
top of the infested material in the bin, and the lid tightly 
closed down. Its fumes permeate all the material with fatal 
results to every kind of insect life. The fumes must not be 
inhaled by the operator, and it is most important that no light 
should be brought near till the smell has quite passed away 
after opening the bin, for the bisulphide is extremely 
inflammable. 
There are cases which can be best dealt with by the appli- 
cation of heat — by stoving or baking the infested matter. In 
last year’s report the results were given of some experiments 
on the temperature necessary to kill certain mites without 
injury to the material in which they occurred. 
If a larder or store-house becomes infested by any of these 
household pests it is best to have it thoroughly cleaned out and 
washed as far as possible with dilute cai’bolic acid. Spraying 
with benzine is sometimes recommended. 
The bacon beetle can be specially troublesome in a larder 
or a grocer’s store if its first a^ipearance is not immediately 
noted. Its occurrence on a ham or a side of bacon is not in the 
least an indication of unsoundness ; it only demands food of a 
fatty nature. If observed at once the attacked portion may be 
