71 



is the main reason of the high mortality in man in the Congo due to 

 trypanosomiasis. The small cattle of those regions of French West 

 Africa where Glossina morsitans occurs also supply a very good instance 

 of this. The infection is latent in these native cattle because they are 

 allowed to live and pasture without restraint, and therefore remain in 

 good condition. The same breed suffers in districts where food remains 

 plentiful but water is scarce, so that the physiological equilibrium 

 is disturbed. In eastern Africa domesticated zebra die of trypano- 

 somiasis, whereas they occur in a wild state in tsetse-fiy regions. 

 Prosperity then remains a palliative, but cannot definitely destroy 

 the pathogenic influences when the external conchtions of their spread 

 by insect agency are not modified. 



The extinction of malaria in France is due, in the author's opinion, 

 to the change in the feeding habits of Anophelines owing to the increase 

 of cattle and the permanent practice of keeping them under cover. 

 Without the " cattle factor " the drainage works would have proved 

 insufficient. If the great drainage works in Corsica had been supple- 

 mented by an agricultural development leading Anopheles to attack 

 cattle instead of man, malaria would not be the danger it is at present. 



Sergent (Ed.), Sergent (Et.), Parrot (L.) & Donatien (A.). Le 

 Paludisme en Corse. Etude 6pid6miologique. — Bull. Soc. Path. 

 Exot., Paris, xiv, no. 10, 14th December 1921, pp. 685-710, 2 maps. 



This is a report of an investigation on malaria in Corsica made in 

 1921, in autumn, the most malarious part of the year. 



Anopheles maculipennis, the only species met with, is abundant 

 everywhere, and was found to have a sporozoite index of 1 -2 per cent. 

 The most dangerous breeding places are in the marshes, river beds, and 

 badly kept irrigation and drainage canals in the eastern plain, and in 

 all running waters found in the other parts of the island, even in the 

 mountains, provided that plants and stones check the current. 



The salt lagoons on the coast of the eastern plain do not harbour 

 the Anopheline because their central portions are deep, teem with fish, 

 and contain no grasses, while their shores are maritime in character. 

 The reservoir of the virus is quite as important as ten years ago. 

 Taking the whole island, the children have a spleen index of 23 -8 per 

 cent, and a plasmochc index of 14-7 per cent. If the population of 

 the eastern plain only is considered, they have a spleen index of 39 • 9 per 

 cent, and a plasmodic index of 26- 2 per cent. 



Bagnall (R. S.). The Siphonaptera (Fleas) of Northumberland and 



Durham. — Trans. Nat. Hist. Soc, Northinnbcrland, Durham and 

 Neivcastle-upon-Tvne, London, N.S., v, pt. 2, 1921, pp. 181-198. 

 [Received 30th January 1922.] 



Much useful information is collected in this paper, which discusses 

 existing literature on fleas, and the investigations that revealed the part 

 played by these insects in the transmission of bubonic plague, with 

 notes on the life-C3'Xle and rearing of fleas and their distribution. 

 A fist of British fleas is given, 32 out of the 45 known species being 

 found in Northumberland and Durham. Records are included of the 

 local fleas and their hosts, and short notes are given on the species that 

 have not yet been recorded from the district. 



