190 



on dark nights. The natives believe that by day a very loud noise 

 and much dust scare away the fly; this method is adopted when, 

 entire herds have to cross a fly-belt, noon being invariably the time 

 chosen. They also have great faith in the repellent properties of a 

 solution of myrrh, but experiments showed that this is not justified. 

 The average life of this fly lasts 3 months. From 7 to 10 larvae are 

 laid at an average interval of 10-11 days. The larva immediately 

 seeks shelter and in the laboratory burrowed into sand to a depth of 

 about f of an inch. In nature the pupae are found under the surface soil 

 beneath bushes in places where the earth is dry. They also occur 

 among the roots of trees, banana plants, etc. In the laboratory 

 the pupal stage occupied 28 days on the average. Some pupae kept, 

 in a room where the afternoon temperature exceeded 85°F. (30°C.) 

 gave rise to adults in a shorter time. A temperature of about 94°F. 

 (35°C.) is fatal to the pupae, if prolonged. They also die if immersed 

 for some time in water or in very damp soil. It therefore appears 

 that G. pallidipes may be combated by clearing the bush near rivers 

 and by building up the river banks so as to prevent flooding. Cleared 

 areas may be converted into meadows, yielding forage for the dry 

 season and affording good grazing, or they may be planted with 

 graminaceous crops or cotton. 



Jarvis (F. E.). On the Occurrence of the Immature Stages of 



Anopheles in London.— Ann. App. Biol., Cambridge, vi, no. 1, 

 September 1919, pp. 40-47. [Eeceived 24th October 1919.] 



In an area of about a nine- mile radius with Charing Cross as its centre, 

 thirty-seven pieces of water were examined, including ornamental and 

 natural ponds, swamps and ditches, for the presence of immature stages 

 of Anophelines. Anopheles maculipennis was found in 16 places, 

 A. bifvrcatvs only in one locality, and A. plumbeus (nigripes) was not 

 found at all. Detailed notes are given of previous records of the 

 occurrence of Anopheles in London [see this Review, Ser. B. vi, p. 175] 

 and on the finding of immature stages of Culicids includmg Cidex 

 pipiens, L., Theobaldia morsitans, Theo., Ochlerotatus dorsalis, Mg., 

 and 0. nemorosvs. Mg. Many of the localities visited were unsuitable 

 for breeding-places, whilst in certain places negative results were 

 obtained where the conditions were apparently favourable. Further- 

 investigation of such localities would be advisable. 



Mellor (J. E. M.). Observations on the Habits of certain Flies, 

 especially of those breeding in Manure. — Ann. App. Biol., 

 Cambridge, vi, no. 1, September 1919, pp. 53-88, 4 charts, 6 figs. 

 [Received 24th October 1919.] 



For the control of flies it is considered that the destruction of the 

 immature stages must be relied upon, as measures directed against the 

 adult can never be thorough or permanent, and perfect sanitation . 

 cannot be carried out until legislation and education are much improved 

 in the British Isles. In certain circumstances, such as the 

 impossibility of obtaining authority to control the breeding-places 

 or if these are too extensive to be dealt with, the destruction of adults 

 will have to be adopted. Previous literature on the subject of the 

 hibernation of Musca domestica is reviewed. During the winters of 



