274 Annual Report for 1906 of the Zoologist. 
would almost certainly not suffice to kill the eggs, and this 
must be done if the treatment is to be of any practical use. 
Besides, the time taken to heat the interior of a small glass 
tube to any given temperature would be no indication of that 
required by so bulky an object as a box of cigars. 
The eggs were too small and too difficult to find for 
individual experiment, and the only practicable method of 
procedure seemed to be to expose the closed box to a given 
temperature for a certain time and defer the examination of its 
contents till any surviving eggs would probably have hatched 
out into mites. 
The details of the experiments, which necessarily extended 
over several weeks, are of no particular interest, but satisfactory 
results were not obtained with a temperature less than 
66° C. (about 150° F.). In boxes exposed to this degree of 
heat for half an hour, and opened ten days later, nothing living 
could be found. The cigars so treated were returned for 
expert examination, and the verdict was that they had not 
suffered the slightest injury. 
Ticks akd Disease. 1 
In December, 1904, Dr. Nuttall wrote : — 
“ Ticks and tick-transmitted diseases promise to offer an increasing degree 
of interest to medical men, zoologists, and those economically concerned. 
Some of the diseases which ticks transmit . . . are amongst the most 
devastating which affect domesticated animals in many parts of the world.” 
The importance of external parasites as transmitters of 
disease has been brought home to every one by the now 
classical researches on the connection between malaria and 
mosquitoes of the genus Anopheles. Ticks have been for a 
long time under suspicion, though until quite recently nothing 
very definite was proved against them. The ill effects which 
were believed to result from their bites were attributed to 
“poisonous properties,” and some species, such as the “Mianeh 
bug” (Avgas pensions), had a particularly evil reputation. 
We now know that in the case of quite a number of ticks 
the suspicion is only too well grounded ; that besides causing 
irritating wounds by which septic matter may gain access, they 
are capable of communicating certain definite diseases from 
sick to sound animals ; that the germs of these diseases may 
remain alive in the body of the fasting tick for months or 
years, or may even be present in its eggs and the larvae to 
which they give rise, making the second generation no less 
dangerous than the first. 
It is not surprising, in view of recent discoveries, that 
attention should be seriously directed to this group of external 
1 See also pp. 71 and 86 of this Volume, 
