36 EUPERT W. JACK. 



and there was no subsequent reason to believe that " fly " occurs in the vicinity. 

 Many cattle are used on the roads in and out of Gatooma, and if fly occurred the 

 fact could not remain hidden. 



III. Chicago Mine. S. bank of Msweswe River and about 5 miles E. of railway 

 line. Season 1909-10. 



Thirty-six oxen had been at work near the mine for two years, drawing crushing 

 material from a shaft about a mile from the mine. The only time when any of them 

 were away was when four oxen drew a Scotch cart to Gatooma and back about 

 a month before Christmas 1909. The first case was noticed in March 1910 (diag- 

 nosed by Bevan). At the time of my visit, 6th April, five cattle had died and at 

 least ten more were " struck." S. calcitrans and Lyperosia sp. were extremely 

 numerous about the cattle. The writer could find no sign of tsetse in four days, 

 and there has been no subsequent reason to believe that fly occurs at this spot. 

 Cattle have been working on other mines near by for years, but early in 1909 fly- 

 struck cattle were brought to the Lydia Mine, which is only a short distance across 

 the river from the Chicago, and may have initiated the outbreak. The nearest 

 known fly belt is 12-15 miles distant in a straight line to the north. 



IV. M.'s sivine. Farm on N. bank of Umfuli River, on E. side of and adjacent to 

 railway line. Visited on 15th November 1911. 



A number of sows had been on the farm for two years. The first death occurred 

 on 15th October 1911, and fifteen had died up to time of the visit, as well as one 

 boar. A large number of young pigs on the farm were all healthy, and a number 

 of cattle there also remained unaffected. Tabanus taeniola was very abundant on 

 the cattle at the time of the visit, but did not pester the swine much. S. calcitrans 

 was abundant on the swine. This farm is about 10 miles from any part in which 

 one would expect to see tsetse, but the fly was at that time probably carried occa- 

 sionally close to Hartley, which is about 3 miles distant from the farm. The 

 immunity of the cattle, apart from other facts, practically proves that something 

 other than tsetse was responsible for the spread of the disease amongst the pigs. 



(N.B. — Bevan is doubtful as to the trypanosome in the swine being identical with 

 that affecting cattle in the district, but states that morphologically it belongs to 

 the T. pecorum group.) 



V. S.'s & G.'s swine. Adjacent farms on the Umfuli River. S.'s farm is also 

 adjacent to M.'s. Date of visit, 29th January 1916. 



Of S.'s swine, three pigs were bought from M. and had remained on the farm since 

 January 1914. On 18th December 1915, 32 sows arrived from East London. A 

 sow from East London died on 15th November 1915, and a second on the 27th, 

 both being heavy in young. On 21st December, 40 pigs arrived from East London 

 (35 sows and 5 boars) To that date, 19 heavy sows and 1 boar had died and two 

 more died during the writer's visit, whilst several young pigs showed symptoms of 

 being " struck." Other pigs died subsequently. Cattle ranged on the farm over 

 the same ground as the swine and all remained healthy. Tabanus fuscipes and 

 Haematopota sp. were and had been very troublesome to the pigs since the commence- 

 ment of the rains. S. calacitrans was moderately abundant, and the pigs were, 

 of course, much infested with lice (Haematopinus). 



