178 



YoRKE (Warrington) & Blacklock (B.)- Food of Glossina 'palpalis 

 in the Cape Lighthouse Peninsula, Sierra Leone. — Ann. Trop. Med. 

 Parasit., Liverpool, ix, no. 3, 31st July 1915, pp. 363-382. 

 Two hundred G. jmlpalis were examined as to the nature of the 

 contents of the gut ; recognisable mammalian red blood corpuscles 

 were found in 14 and nucleated red corpuscles in 2 cases, 7 and 1 per 

 cent, respectively. Man and his domestic animals would supply the 

 former, while birds and lizards are abundant enough to furnish the 

 latter in quantity. In over 90 per cent, of flies, red cells can be 

 distinguished 24 hours after a feed, but only 40 per cent. 48 hours after, 

 while after 72 hours, no definite red cells could be found. Avian 

 corpuscles were found to endure longer, 100 per cent, after 24 hours, 

 60 per cent, after 48 hours and 40 per cent, after 72 hours ; 64 flies 

 w^ere used. What food, other than blood, tsetse-flies take, is difficult 

 to decide, but recorded observations tend to show that plant-juices 

 are consumed. Experiments as to whether starved flies could take 

 up fluid directly, gave negative results, and Rodhain's method of causing 

 the flies to take up fluid through a membrane of fresh rat's skin was 

 tried. The flies were kept at a temperature of 80° to 86° F., and it 

 was found that neither shed blood nor other fluid which is not covered 

 by a membrane, can be imbibed by G. palpalis. The fly can however 

 take up through a membrane of fresh skin, not only blood and various 

 dilutions of it with normal saline, but also suspensions of red blood- 

 cells in normal saline, and solutions of haemoglobin (both freshly made 

 from red blood cells, and the dried crystalline preparations of com- 

 merce) in distilled water. Fluids other than blood, such as solutions 

 of sugar, sodium chloride, and glycerine, in water containing a small 

 quantity of a dye (methylene blue, neutral red or fuchsin), are also 

 taken up through a membrane of fresh skin, but not so quickly or so 

 readily as is blood. G. palpalis exhibits a definite selective taste for 

 the various fluids presented to it under the membrane, blood, red cells, 

 and haemoglobin solution being much preferred. The attractive 

 element in the blood is the fraction of the red cells soluble in water, 

 probably haemoglobin. Examples of G. palpalis which have been 

 starved for a day or two, can often be seen to insert the proboscis 

 repeatedly into oranges, bananas or other fruits which may be offered 

 them, and it is concKided that this fly in nature, may, under certain 

 conditions, imbibe fluids other than blood. 



YoRKE (Warrington) & Blacklock (B.). The Reservoir of the Human 

 Trypanosome in Sierra Leone. — Ann. Trop. Med. Parasit., Liver- 

 pool, ix, no. 3, 31st July 1915, pp. 383-390. 

 It is contended that Kingborn and Yorke have shown that the chief 

 reservoir of the human trypanosome of South Central Africa (.7'. rho'le- 

 siense.) is the antelope and not man. The antelope is toleraiit of the 

 infection, while man is not, and the distribution of-antelopes in South 

 Central Africa practically coincides with that of Glossina morsitans. 

 In Sierra Leone, the infection is extremely chronic and man is therefore 

 a more constant and dependable reservoir than in Rhodesia or Nyasa- 

 land ; further, large game is more or less rare in Sierra Leone and the 

 prevalent fly is G^. jtiaZ/xj^«5, which frequents watercourses and therefore 

 the haunts of man more closely than the ubiquitous G. tnorsitans. 



