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Bagamoyo was reached on 5th September, and I set out on trek forthwith. For five days the route ran through thin woodland interspersed with grassy slopes, on which herds of native-owned cattle were here and there dotted; but on the sixth day, two miles east of Ngerengere, an important station on the Central Railway, and about a hundred miles west of Dar-es-Salaam, a thorn bush zone On the following was entered, and morsitans appeared in considerable numbers. day the journey was continued to Mikesse, some fifteen miles west of Ngerenegere, along a road south of the railway; along its whole length the fly was excessively annoying, pallidipes being present as well as morsitans, though not so numerous, and, rather to my astonishment, a few brevipalpis, two of which, one a female, The bush in which the bit me at 11.0 a.m., the sun being very bright and hot. latter insects occurred was unusually dense, but, so far as I could ascertain, there was no water near by.

9. Morogoro, the end of the journey, was reached on 17th September. Two days spent at Morogoro in the tsetse survey of the neighbourhood resulted in the discovery of abundant morsitans some two miles to the north of the town in the usual thorn bush country, extending back, as I was informed by transport men, for fifteen miles, throughout which the fly was reported to be troublesome.

I visited also the German Government stock farm situated about two miles south of the town and about five hundred feet up in the hills. The man in charge, a Swiss, formerly in the employ of the German Government, informed me that prior to the War the cattle had thriven there for many years, but that recently, owing, as he thought, to the constant movement of troops and animals into the town through the fly area, the fly had been taken on the farm, with the result that there had been progressive loss in the stock.

10. On 19th September I received instructions to return to Dar-es-Salaam, and attempted to do so by the old road, more or less parallel to and south of the Central Railway, along which I marched for four days, meeting on 20th with swarms of morsitans in the neighbourhood of Kanghala, about thirty miles east of Morogoro, and fifteen miles south of the railway. But the track, which had evidently not been in use for many years, became less and less defined, undergrowth having sprung up, and so I was then compelled to strike due north for the Bagamoyo road once again, along which I returned to that town; and a further two days' trek along the thirty-six miles of coast, during which I saw no flies, brought me into Dar-es-Salaam.

11. It had become increasingly obvious that no practical value had resulted from my tsetse surveys. It was hardly to be expected that military exigencies could be modified by the presence of the flies; and, moreover, by this time, so great had been the losses in animals, largely, I am sure, owing to trypanosomiasis. that the bulk of the mounted men were on foot, horses were not being to any large extent replaced, and the ox convoys had almost given place to mechanical transport. I did not feel, either, that my work if continued would have any value subsequent to the War, since the fly distribution had undoubtedly been extended as a result of military movements, and would almost certainly become again modified in the direction of a restriction of the fly areas when the country reverted to a more normal state of affairs. The Germans being hemmed up in a comparatively small corner of the country, and the end of the campaign within sight, I therefore tendered my resignation to the Inspector-General of Communications, under whose direct instructions I had latterly been, and who, on my discussing the position with him, agreed unreservedly with the view I expressed, so that on 17th November my resignation was accepted.

It was a lamentable reflection that so much time and energy had been wasted to so little purpose. A certain value doubtless had resulted from one's surveys in reference to animal camps, and one's further conclusions as to results could only have been arrived at as the outcome of the experience.

12. Facilities in regard to bionomic observations were almost entirely lacking. The following points were, however, noted :--

(a) Morsitans had undoubtedly become more widely distributed along the It occurred, for instance, in thin bush roads as a result of military movements.

in the neighbourhood of a large pool in the partially dried up Muruangoin River, at which, previous to the War, the Masai had been in the habit for years of watering It occurred sparsely, also, along the last their cattle with impunity in the dry season. fifteen miles from Sanja River into Lolkissale, an average elevation of 4,800 feet

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in more or less open country, with merely a few dwarfed trees scattered here and there, and in country of a similar character between Lushomo and Handeni. spread to the Government farm at Morogoro has already been commented on.

(b) Such game as there might have been in the vicinity of the roads in the fly area had long since been driven away, partly, doubtless, owing to the constant military movements, and partly by the merciless fusilade directed against any living creature that offered a target by small irresponsible parties of men proceeding to or from the actual scene of operations. Very rarely were any animals seen even at a distance on the plains, and little spoor or other evidence of their presence was found, whether in the wet or in the dry season.

(c) The flies in an area undoubtedly lurked more along the roadsides than elsewhere, probably attracted by the passage of moving objects, and certainly by the beasts, and they were more numerous on the return journeys than when I set out, doubtless from the constant operation of the same causes, and to some extent from an actual increase in numbers, breeding being favoured by the readil obtainable food supply.

(d) Just south of the Muruangoin River one pallidipes, and one only, a male, was secured in the course of a long hunt, with numbers of morsitans.

(e) Morsitans, pallidipes, and brevipalpis, the last biting by day, were taken together in one area.

The country in which I found large swarms of pallidipes was exactly of the same nature as that in which, from my experience in Nyasaland, I should have expected to find morsitans.

(g) In two localities, seven miles north-east of the Tarengere River, and about forty-four miles south-west of Lolkissale, and again in the vicinity of the same river about ten miles to the west of this locality-probably one and the same fly area-a few female morsitans were captured, which exhibited two forms of In the one case there breaches of surface on the ventral aspect of the abdomen. appeared to be a minute excrescence between two of the segments; in the other a dark patch with a central depression suggested a possible puncture with dried effusion of fluid round it. Unfortunately time did not permit of a careful study of the conditions; and the scanty material which was available for examination by an expert at home has been still further reduced by the depredations of ants.

(h) Morsitans pups were found as readily as in Nyasaland, the same character of breeding place being selected by the fly.

(1) In addition to tsetses, Stomoxys of various species occurred in great numbers at all camps, sometimes goading unfortunate picketed animals almost to a state of frenzy, so that a watch had to be kept that, in their endeavour to get relief from the torment by rolling, they did not strangle themselves with their picket ropes. The Deputy Director of Veterinary Services was, of course, duly notified as to the presence of these flies, as the probability of the mechanical trans- mission of trypanosomes from infected to healthy animals was obvious.

Any adequate control of the pests was out of the question, owing to the enormous quantity of dung scattered over the country, but at the veterinary hospitals and horse camps, at least, systematic attempts were made to dispose of the droppings in the vicinity.

(1) On the southern slopes of Kilimanjaro in May, the end of the wet season, very large numbers of dead Orthoptera, some Locustidæ, but chiefly Acridians, of the genus Zonocerus, or one closely allied to it, were found in a mummified state on the plants on which they had been feeding, imagos and immature forms alike having perished. As there was no evidence of parasitism by large insects, I imagined they had probably died from some infective disease.

(k) A considerable collection of insects was made, including Tabanidæ, which seemed most abundant in thin woodland and plain country.

I have, &c.,

The Director,

Imperial Bureau of Entomology.

N 2

W. A. LAMBORN, Entomologist under the Imperial Bureau.