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PUBLIC RECORD OFFICE

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C.O. 885

22 PUBLIC RECORD OFFICE, LONDON

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might be possible to make the main trunk road through Liwonde fly free by clearing along either side of it (without fencing), and thus provide a safe road for man and beast to up-country stations, and the recommendations in paragraph 7 might be carried out in this area.

Paragraph 7. Although there is little doubt that, were natives in the Dowa infected area encouraged to kill the game, a very considerable diminution in the number of game would be effected, it is probable that the game would be reinforced by migration from the broken hill country bordering the plain and much of the game from the plain might escape to the hills-where hunting is difficult-returning only at night to the plains to feed, so that it is quite possible that such a proceeding might not result in actually clearing the plains of game. As regards the Dowa district, therefore, I should consider the success of a game destruction scheme as very uncertain. A radius of some miles round the township of Fort Johnston would seem to be a more promising locality; game and tsetse fly are frequently to be seen, I believe, within a short distance of Fort Johnston, and the results on the prevalence of tsetse fly after driving back the game could be conveniently observed there. In the case of Chiromo, where a two-mile strip along the Ruo River was put outside the reserve some years ago, a large amount of game was killed close to the township, and the survivors soon retired back into the Elephant Marsh. A similar result might, I think, be anticipated at Fort Johnston by granting licences to a number of natives to hunt within a radius of, say, ten miles of the township.

J. B. DAVEY,

23rd July, 1914.

Medical Officer.

MEMORANDUM ON THE PROPOSALS OF THE SLEEPING SICKNESS INTERDEPARTMENTAL COMMITTEE.

By Dr. H. S. Stannus.

ACTING PRINCIPAL MEDICAL OFFICER,

ON reading through the Colonial Office despatch and Report of Committee the following points occur to me.

1.

One can only regret that the Royal Society Commission under Sir D. Bruce has not given more definite information about human trypanosomiasis in this country and settled several of the points which now arise, such as whether man may or does act as a reservoir of the human trypanosome.

2. To ascertain the point now is a much more difficult matter; the investi- gation can only take place at Kasu. Dr. Conran is there without any colleague and with no assistance such as the Commission had. The work can, of course, be done, but if started by Dr. Conran he will not be able to see it through, as he goes on leave in November, and such an interruption may cause delay. Who is there to take over the work? Are funds available for affording the necessary assistant staff? Are experimental animals available?

3. Ref. Paragraph 4. Are the means available of examining a series of bush-pig-To answer the question proposed in paragraph 4 a series of examina- tion of blood and of inoculations into series of animals, with the making of measure- ments of thousands of trypanosomes, would have to be undertaken, followed by a series of transmission experiments with laboratory-bred fly. A large staff, such as the Royal Society Commission had, would be necessary. This is putting aside the question whether any aardvark would be forthcoming.

And when done, of what value would be the results? Some animals might be added to the list of incriminated animals, but the list is long enough and remains only incriminated, no definite proof being established that any animal trypanosome is the same as the human trypanosome.

4. Ref. Paragraph 5. Experimental game destruction.-Everyone feels that such an experiment might yield valuable evidence on the bionomics of tsetse fly, but unless undertaken with scientific precision the results are only likely to prove unsatis- factory. The experiment should be watched by a staff of experts-medical men and entomologists.

Cost is another point of first importance. I have seen miles and miles of game fences made of logs in West Nyasa and Momberas districts, and residents in these

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districts might be able to give information as to the cost and efficiency of them. As to locality: the infected area naturally suggests itself, or some of it.

An area behind Rifu is also a likely place. The Livingstone Peninsula, I believe, would offer many advantages, but it is a question which, I suggest, might be discussed by a committee of the Administrative, District, and Medical Officers.

The Zomba-Blantyre road experiment suggested by the Chief Veterinary Officer I think of little value.

The number of head of game permanently in the neighbourhood is small and probably limited to the smaller antelope, which are difficult to eliminate; while this is the case, as a rule, herds of the bigger antelope do wander up from the lower grounds from time to time, and free shooting or anything else will not prevent them. The conditions are so uncertain that no deductions would have any value.

5. Ref. Paragraph 6. Clearing operations.-In my opinion to be encouraged by all possible means. Agricultural development, following the opening up of the country by railway, will help. Little, I fancy, can be done to make natives clear without payment, and expense immediately is prohibitative. Also, it has to be remembered that a country devastated of its timber and bush becomes non-pro- ductive and barren, like large tracts of Northern Angoniland, as the result of forest clearing for growing beer-crops.

6. Ref. Paragraph 7. All will agree; no experiment is of any use unless it be watched by experts, but clearing of game away from villages and neighbour- hood, should, I think, be allowed and encouraged. Anyone who has a knowledge of conditions up country knows of the large amount of damage done to crops by game, which, in itself, is sufficient reason for native hunting to be permitted.

7. Ref. Paragraph 8. Entomological research-Without this important branch of research anything is at a standstill; personally I cannot help feeling that it is a pity that the research at present taking place in British East Africa is not being undertaken in Nyasaland (Fiske).

8. Ref. Paragraph 9. A bigger medical staff is required for this work with greater assistance; with a larger number of men some could undertake part of the entomological work.

9. The problem has only been looked at from one point of view to a large extent, and that based on a preconceived idea with regard to the evolution of the epidemic.

Sir D. Bruce, before he visited Nyasaland, gave out the idea of long-established endemicity of human trypanosomiasis. To this idea he has adhered, and others have accepted the idea with, as far as many of us can see, very little evidence. To me the question appears to be one bristling with problems awaiting solutions, of which the Royal Society Commission's confirmation of Kinghorn and Yorke's work was only one.

There is one point which, I think, is fallacious. In section 126 of Report it is stated that "its incidence on the population is slight"-referring to human trypanosomiasis. I believe the proper way to look at the figures for Nyasaland is to compare the number of cases with the population of the villages in which the cases occur. I think it will then be seen that the figure looks very like an epidemic rate, and not like an old endemic with slight incidence.

H. S. STANNUS,

Medical Officer.

Enclosure 2 in No. 92.

NOTES ON TSETSE IN THE NGARA SUB-DIVISION OF THE MARIMBA DISTRICT.

By Dr. G. Prentice.

I think it was about the end of 1907 that I first observed and reported upon the presence of tsetse fly on the Mpangara, a tributary of the Dwangwa. It had crossed the watershed from Rhodesia at an altitude of about 3,000 or 3,600 feet.

We next found it on the upper waters of the Lingadzi, another tributary of the Dwangwa (1908).

Mr. Hall, of Rhodesia, found it on the Rhodesian border, near the watershed of the northern tributaries of the Dwangwa. He wrote me about it, but I cannot

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