48 W. A. LAMBORN. 



artificial breeding places. From beneath nine of these no less than 59 living pupae 

 of morsitans and 39 cases were obtained a few days ago [January 1916], the remaining 

 three trees being unapproachable on account of floods. The number of pupae there 

 obtained have exceeded expectation, and it would almost appear as if the flies had 

 exercised a judicious selection in their choice of places for the reception of their pupae, 

 preferring artificial ones which fulfil presumably all their requirements to the natural 

 ones, many of which cannot in respect of drainage, protection from sun and rain, 

 etc., be as wholly satisfactory. The country at Lingadzi is of the type most favoured 

 by the fly in this Protectorate. 



From the twelve similar breeding places comprising ten different species of trees 

 felled near Rifu 20 pupae and 19 pupa-cases were collected at about the same time, 

 no tree in particular being favoured. A larger number was hardly to be expected 

 in this locahty, owing to the stony nature of the soil and the numerous natural breeding 

 places afforded by rocks. 



Thirty of the artificial breeding places arranged on a large and systematic scale 

 over two square miles near Monkey Bay, which were recently searched, yielded 98 

 pupae and 34 pupa-cases, an average of about four to each place. But, as I have 

 before noted, there has been a very marked falling off in the numbers of the flies in the 

 neighbourhood recently, so much so that one may noAV pass along the road running 

 north with almost complete immunity from attack, whereas nine months ago a buzzing 

 swarm of flies invariably followed in pursuit. This, as I believe, has been brought 

 about by the agency of the parasite Mutilla gJossinae, Turner, which in August and 

 September was found to have parasitised a very high percentage of the pupae. It is 

 not attributable to any withdrawal of the game, for several small herds of water-buck, 

 female kudu, and three large herds of eland, besides wart-hog and the smaller 

 antelopes, bush-buck, impala and duiker were to be found almost day by day. 



The possibility of checking the flies through artificial breeding places has therefore 

 been estabhshed, the results at Lingadzi almost suggesting that control could be 

 effected without the expense of ehminating other than the larger natural breeding 

 places. One realises of course the impracticability of the application of the method 

 over the vast fly area of Nyasaland, which, as I see in the report of the Sleeping 

 Sickness Commission of the Royal Society, is estimated at 5,000 square miles, but it 

 would certainly seem feasible to empk)y it over small areas, those in proximity to 

 trunk roads or to important centres. The high road from Zomba to Fort Johnston, 

 for instance, runs for several miles to the north of Liwonde through a fly area, which 

 then deviates from the road, the country being less favourable to the fly. To the east 

 the area is limited by the river Shire at no great distance, and to the west by hills and 

 bv more open country, not more than a mile or two away, so far as memory serves 

 me. It should be possible to make a broad clearing at either end of the area where 

 it touches the road, and then artificial breeding places should be constmcted within 

 the area so cut off. The possibilities of the transfer of flies across the clearings by 

 moving game might perhaps be obviated by means of a wire fence. 



Some similar measure may be required when, as anticipated, the projected railway 

 from Blantyre is carried north through the fly area. I have repeatedly noticed in the 

 Southern Provinces of Nigeria that the railway is responsible for the transfer from place 



