101 



(Acahjpha), round which a great number of pupae were always to be 

 found, have been mostly washed away, so that here the breeding 

 area has been reduced to a fraction of what it used to be. On Bulago, 

 where the flies were never very numerous, the decrease in proportion 

 is not so great ; this is probably due to the less detrimental effect of 

 the rising lake owing to the much steeper shore. Here pupae were 

 only found where the sand or dusty humus was dry to a depth of 2 

 inches below the surface. On Damba in former years there were 

 numbers of bushes of Triumfetta and Acalypha growing outside the 

 actual forest zone, and under these pupae were found in large numbers 

 in the dry white sand. In July 1918, 10 men working 4 hours obtained 

 only 1,680 pupae, the majority of which w^ere found around the 

 roots of a large tree at the edge of the forest belt, the trunk of which 

 was just above the 1917 water-level. Wherever dry sand and shade 

 were found, pupae were also found, the majority being within a few 

 yards of the high-water mark. The conclusions arrived at by Fiske 

 in 1914, that if the breeding grounds are restricted, there will be a 

 corresponding decrease in abundance of fly, were borne out by the 

 events of 1917-18. As the lake recedes the fly w^ill become more 

 abundant ; this may be prevented by clearing away the Acalypha 

 and Triumfetta shrubs so that the sun may have free access to the 

 breeding grounds. A permanent rise of the water-level might elimi- 

 nate G. palpalis from the Victoria Nyanza. Certain of the islands 

 are suitable for cattle grazing and with judicious treatment could 

 thus be reopened to a native population. The Ripon Falls are the 

 only outlet to Lake Victoria, and the erection of a permanent dam 

 at this point has been considered and found feasible from an 

 engineering point of view. 



KiNOSHiTA (S.). Chosen-san Kiuketsu-sei Cidicoides ni fsukite. [On 



a Korean blood-sucking Cidicoides.] — Dohulsugaku Zasshi 

 {Zoological Magazine), Tokyo, xxxi, no. 365, March 15th 1919, pp. 

 87-88, 5 figs. 



The male of Cidicoides miharai, recorded in a former paper [see this 

 Review, Ser. B, vi, p. 224], is here described. 



Cowan (Col. J.) & Mackie (Capt. F. J.). A note upon the Modes of 

 Infection in Bacillary Dysentery. — Jl. R.A.MC, London, xxxii, 

 no. 3, March 1919, pp. 209-214. 



Although the investigations made in 1916 in Alexandria to ascertain 

 the means by which dysenteric infection is disseminated were not 

 completed, one of the conclusions arrived at was that flies play a 

 considerable part in spreading infection by contaminating food and 

 drink. Experiments made w^ith flies fed on dysenteric stools confirmed 

 this view, though those made with flies caught in the latrines of the 

 dysentery wards were negative. As a result of these experiments 

 the danger of infection from this source is not considered serious, 

 especially as the means adopted to combat flies and prevent their 

 access to food and drink have proved successful. 



(C568) ... ^ 



