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24 hours and emerged during the first week of April, some being 

 Fannia canicularis and others Musca domestica. Some larvae were 

 found hibernating at a depth of two feet. 



From these observations it appears that the fly either passes the 

 winter in the pupal stage, or that the larvae may have the power of 

 hibernating with intervals for feeding during the spells of warmer 

 weather. Ova deposited on manure heaps late in autumn and covered 

 over, may, owing to the warmth generated in the manure, give rise 

 to larvae that feed and eventually pupate. The pupae may remain 

 dormant till spring, or be hatched by a brief spell of warm weather, 

 which may account for the presence of adult flies in winter. Hence 

 it follows that if the spread of flies is to be prevented, manure should 

 either be burnt or spread out in thin layers, since covering the heaps 

 Avith earth, or even sowing the surface with grass or other, seeds, 

 appears to be of doubtful value once the eggs have been deposited in 

 the manure. 



The Warble Fly. — Jl. Dept. Agric. Tech. Instruct. Ireland, Dublin, xvii, 

 no. 4, July 1917, pp. 657-658. 



In Ireland there are two varieties of warble fly [Hypoderma] that 

 cause loss to farmers by injuring the flesh of cattle, reducing the 

 milk-producing power of cows and rendering the hides worthless for 

 tanning. During the fly season, which may last from the middle of May 

 till the end of August, the female lays eggs on the hairs of the sides, legs 

 and feet of cattle, rarely on the back. The eggs are hatched in four 

 or five days and the young maggots bore into the skin, wander through 

 the body for several months, and from December onwards appear 

 beneath the skin of the back forming round tumours or warbles. Later 

 the skin is pierced, and from February to June or July the maggots 

 emerge, fall to the ground and eventually develop into the flies of 

 next summer. 



The best method of control is by destroying the maggots by squeezing 

 them out. This can be done more easily in wet than in dry weather 

 and the skin can be made more pliable by washing with salt solution — • 

 i lb. salt to 3 gallons of water. The skin heals quickly, but, where 

 several maggots have been removed from a small area, an antiseptic 

 dressing is advisable. The practice of smearing the backs of cattle 

 with a sticky substance mixed with a poison has also been advocated, 

 but no mixture can be recommended with confidence as being deadly 

 to the maggots and harmless to the cattle. Squeezing-out should be 

 thoroughly done three or four times in the season, and, if systematically 

 carried out for a few years throughout the country, should greatly 

 reduce the number of these flies and finally exterminate them. 



Atkin (E. E.) & Bacot (A.). The Relation between the Hatching of 

 the Eggs and the Development of the Larvae of Stegomyia fasciata 

 {A'edes calopus), and the Presence of Bacteria and Yeasts. — 

 Parasitology, London, ix, no. 4, 27th July 1917, pp. 482-536. 



An elaborate series of experiments was conducted with the object 

 of testing the old and popular belief held in all mosquito-ridden 

 districts, that mosquito larvae exert a clearing action in turbid water 

 and cannot live in clear water. 



V 



