236 THOMPSON YATES LABORATORIES REPORT . 
approximately equal. Nevertheless, out of a large number of Anopheles collected 
inside European and native quarters but very few males were present ; from notes 
made at the time we counted only 22 males to 293 females, but the proportion is 
probably only about half that, since many females were taken without note being 
made of their number. 
As to what becomes of Anopheles during the day, no exact facts have been 
observed, and whether the majority remain hidden in the darker parts of habitations, 
or hide among vegetation, is not absolutely certain. But after sunset, clouds of 
mosquitoes were often observed flying and hovering in characteristic flocks in the 
neighbourhood of native huts, about eight feet above the ground. On capturing 
and examining many of these, all were found to be Anopheles males. 
In native huts it is never difficult to obtain Anopheles females ; a large number 
are always found, for example, in the Kroo boys' huts, while perhaps in the European 
dwelling-house only an occasional one can be caught. In fact, we found it a good 
practice in many parts where Anopheles were apparently scarce in European quarters^ 
to provide the native boys who acted as our servants with mosquito curtains (they 
often craved for these) ; a number could be obtained in this way every morning 
inside the curtains, which had been badly applied by the ' boys.' Many of the Kroo 
boy servants make themselves rough curtains of any ' cloth ' they can obtain ; these 
invariably provide a supply of Anopheles. 
It is popularly believed that mosquitoes, and more especially those of the 
genus Anopheles, bite only during the evening and night. It is common experience 
that many of the genus Culex bite during the day time ; and, as to Anopheles, we have 
often observed these insects alight on different parts of us, and feed voraciously, in 
broad daylight. It probably depends very considerably on circumstances. If a feed of 
blood cannot be obtained at evening or night time when the great majority of these 
insects feed, then they will bite in the day time. For instance, in offices occupied 
only during the day time, we were able to find Anopheles with distended abdomens. 
In fact, in the darker parts of the rooms, under tables and desks, behind chairs, etc., 
Anopheles were always to be found ; and here they rest until an opportunity of feeding 
is presented to them, be it day or night ; or maybe they are disturbed, fly about, and 
often attack the intruder. 
Considerable evidence has now been accumulated to prove that the distance 
which is traversed by a mosquito is never very great, and extremely rarely reaches so 
much as half a mile. The fact that their breeding places are always within a short 
distance of some dwelling, and have only very rarely been found at a distance even 
of half a mile, negatives the probability of a long flight. The outbreaks of malarial 
fever on board ships whose crews had never left the ship, were explained when 
mosquitoes of the genus Anopheles were collected on board ships in malarious districts; 
and cases occurred which, from their long period of incubation, required as an 
