304 STOMOXYS AND NAGANA. 



Possibly some of these statements refer to the Fayfim, in Upper 

 Egypt, Avhere, as I am informed by my colleague, Dr. C. W. 

 Andrews, the Arab camel-drivers declare there is a fly in the 

 months of May and June which kills camels ; * so convinced are 

 the drivers of this, that they will not allow their camels to visit 

 the district during the dangei'ous season. If this fly has any 

 existence in fact, it seems scarcely possible that it can be a 

 Tsetse, since the Fayiim, which lies approximately between 29° 

 and 29^ 30' N. latitude, is far removed from the nearest known 

 habitat of Glossina. It is more probable that the fly, if it 

 exists at ail, is either a Stomoxys or Lyperosia, or else a horse-fly 

 (Tahaniis, Hsematopota, or Fangonia) ; and in connection with the 

 iirst-mentioned genus, it may be remarked that the British 

 Museum collection contains a series of specimens of a species 

 of Stomoxys, which were brought home by Dr. J. W. Gregory 

 from Ngatana, British East Africa, where he stated that they 

 killed his camels. Moreover, a fly that is obviously a species of 

 Stomoxys was declared by Mr. F. J. Jackson [lip] to be "very 

 plentiful " in the forest on the banks of the River Lumi, at Taveta, 

 British East Africa, where it " worries beasts to such an extent 

 that they are unable to eat, and die." In this case, as has 

 already been pointed out (see Chapter VI., Bibliography, p. 211), 

 the mortality may really be due to a Trypanosome. The late 

 Captain A, G. Haslam, at Machakos, in June, 1898, found the 

 living Trypanosome of Tsetse-fly disease in the posterior part of 

 the abdomen of specimens of two species of Stomoxys caught 

 sucking the blood of mules sufiering from the disease ; and in a 

 letter dated July 3, 1898, which he sent to the author with some 

 of the insects, he stated that he had "caught these flies on every 

 kind of animal, including gazelles, wildebeeste, and all domestic 

 animals, and also on meat exposed for a few seconds." Captain 

 Haslam went on to say : " Animals do not object to them much 

 after the preliminary stab with the pi-oboscis. They remain 

 sucking for several minutes, and bulge out their abdomens with 

 blood. I am now engaged in experiments to show whether these 

 flies I send you actually inoculate other animals with the Tsetse 

 disease." The lamented death of the writer, which took place 

 Vjut a fortnight after the date of this letter, f prevented these 

 experiments from being completed ; but it may be pointed out 

 that any blood-sucking fly feeding upon the blood of an animal 

 suffering from Nagana, in which the parasites were numerous, 



* This insect, whatever it may be, must not be confused with the 

 camel bot-fly {Cephalomyia nnaculata, Wied. — Family QLstridae), the 

 larvse of which are very frequently met with in the nostrils of camels, 

 but do not appear to be injurious to the animals. When mature 

 they are sneezed out by the camels and pupate in the sand. (For a 

 figure of the fiy, see Sharp, Cambridge Natural History, Insects, Part II., 

 p. 515). 



t See page 100, note. 



