— 56 — The types imported in this manner, which were previously foreign to Khar¬ toum, were as follows :— Anopheles pharoensis. Anopheles squamosus. Anopheles mauritianus (paludis). Mucidus scataphagoides. Culex quasigolidus (tenax var. maculipes). The type common in Khartoum is Anopheles gambia (costalis).

ANTI-MOSQUITO WORK.

The total cost of this work within the Province was £e. 2084.501 m/ms. i.e. labour £e. 1615.681 m/ms., larvicide £e. 468.820 m/ms. The total number of infections found was 7,348 of which 5,757 were found in Khartoum district, 477 in Khartoum North, and 1,114 in Omdurman.

Of the total infections found 211 were in the pupal stage and 689 were eggs. The pupal infections show a decrease of 178 compared with 1927.

As previously intimated we are now concentrating on a much extended area and more frequent inspections are being carried out. This has been made possi¬ ble by the Headquarters and the Rural District staff working in conjunction with each other. Even then it is a case of working against time on many occasions owing to the insufficiency of trained men, and leave has been entirely suspended meantime.

In Omdurman 21 public wells and 9 borrow pits were filled in during the year, 1,888 cubic metres of material being used for this purpose. A smaller sum than in former years was made available for this work and for this reason the total number of wells and pits filled in was less than in former years. It is to be hoped that adequate provision will annually be made for this necessary work.

Following the systematic filling in of wells, applications for the town water supply were received. In each instance the premises to be connected up were inspected and suitable sites selected for the placing of taps.

Tables will be found at the end of this report giving details of the mosquito infections found during the year.

The following tables show the incidence of primary malaria by sexes, na¬ tionalities and age periods and also cases amongst British troops and types of parasites.

Sexes:— Males .. • • a a • • 300 Females a a a a • a 59 Nationalities: — British . . a a • • a a 194 Other Europeans a a a • - • 10 Egyptians and Syrians a a 13 Natives of the Sudan a a a a a a 139 All others a a a • • • 3 Age Periods:— 0-1 1-5 5-10 10-20 20 - 40 40 - 60 0 ver 60 Undefined 5 30 20 62 199 12 1 30 Type of Parasites :— Civil Troops Malignant Tertian .. . . 205 83 Benign Tertian 75 42 Quartan 45 26 B. T. and M. T. 2 9 +ml Undefined . . 32 14