Reports to various Correspondents. 
5 
Report on a visit to Higham Hall , Woodford , 12 th June, 1903. 
The annoyance caused by Mosquitoes in your neighbourhood is due 
at present to the presence, amongst others, of one of our largest British 
mosquitoes, Culex diver sus, Theobald. (Other species occurred in greater 
numbers later, vide p. 7.) 
This species, previous to the last few weeks, has only been once recorded 
(in the neighbourhood of Tunbridge Wells). Other species will probably 
occur later. 
During the last week complaint has reached the Board of Agriculture 
that this same species of Cidex has been causing great annoyance near 
Bristol during the last five years. 
At present nothing is known of its life-history, but from its general 
structure I imagine it to be a sylvan species, and not a domestic one, such 
as the common gnat Culex pipiens. 
I could detect no traces of the larvae in any of the natural pieces of 
water or in any of the artificial collections near your house. This is 
probably because the species has not yet oviposited. Nevertheless, a much 
more thorough search should be made. 
In the immediate vicinity of the house the following possible breeding 
grounds were observed : — 
A. Artificial collections of water. 
1. A large overhead tank used for conservatory. (The shed in which 
this is placed is said by your under-gardener to be full of Culex at certain 
times.) 
2. A large tank in stable yard. 
3. A barrel used to receive waste water from a standpipe near stable 
yard and outside the garden. 
4. The overflow from the above into a ditch near by. 
5. Several open pieces of water in connection with the greenhouses in 
the garden. 
6. A large tank partly open on the roof of the Hall. 
B. Natural collections of water. 
1. Two small ponds in meadow below the Hall. 
2. Several small pits in the forest close to the house. 
3. Several small, unhealthy pools and larger pieces of water on the 
common close to the main road. 
4. Higham Lake at the bottom of the meadow, some distance from 
the Hall. 
All the artificial pieces of water are likely places to find Culex larvae, 
and also most of the natural collections. 
I do not anticipate much danger from the lake, and for the present 
should leave that out of consideration. I should advise the following 
provisionally : — 
(1) That the tanks referred to near and on the house, and also the 
open pieces of water in the garden used for greenhouse purposes be closed 
