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to four days. The ntimber of eggs deposited varies from 40 to 248: 

 The larvae hatch in a few hours ; pupation takes place from 6 to 20 

 days later, and the pupal period ranges from 3 to 27 days. From 

 10 to 14 broods are produced during the summer in southern Texas. 

 C maceUaria shows a marked tendency to breed in animals which have 

 recently died rather than in old carcases. The deposition of living 

 young "has not been observed in Texas. This species occurs in great 

 numbers in places remote from any habitation. 



Lucilia sericata passes the winter in the larval and pupal stages 

 and breeds in early spring in decaying animal matter. In summer, 

 oviposition occurs within from 5 to 9 days after the adults emerge 

 from the puparia. Incubation varies from 1 to 7 days, according to 

 the temperature. Pupae are formed in from 3 to 9 days after hatching 

 and adults emerge within 3 to 13 days after pupation. ■ 



L. caesar winters in the larval and pupal stages, the adults appearing 

 in early spring or during warm periods in mid-winter. The pre- 

 oviposition period lasts from 6 to 20 days. The eggs hatch in less than 

 24 hours, and pupae are formed in from 3 to 12 days. The pupal 

 period ranges from 5 to 16 days. Low temperatures may lengthen 

 the prepupal stages for several weeks. 



Phormia reqina is commonly seen in houses during late autumn 

 and early spring. In the Southern States this fly practically disappears 

 during hot weather. It is largely a carrion feeder. Oviposition 

 begins in 7 to 18 days after emergence. The egg-stage lasts from 

 1 to 4 days, and the pupal from 3 to 13 days. CaUiphora erythrocephala 

 is found "in Eastern Texas. The deposition of eggs begins in 12 to 17 

 days after emergence. The incubation period is 24 hours and the 

 larvae begin to migrate from the food 3 or 4 days after hatching. The 

 pupal stage lasts from 7 to 9 days. Cynomyia cadaverina appears 

 together with P. regina in autumn. Food products of animal origin 

 serve as breeding places. The first eggs are deposited from 7 to 20 

 days after emergence, these hatch in 1 or 2 days, while puparia are 

 formed in 5 to 39 days later. The duration of the pupal stage is from 

 6 to 58 days. 



The adoption of remedial measures based on the prevention of 

 breeding in decaying animal matter is difficult, owing to the fact that 

 carrion-breeding' flies are regarded as beneficial scavengers. The 

 appearance of anthrax has compelled the destruction of animals dying 

 from this disease ; destruction by burning has had a salutory effect 

 on the number of screw- worms in some districts. Where C. maceUaria 

 and other flies are prevented from increasing in large numbers, the 

 chances of living animals being attacked are almost negligible. Bury- 

 ing carcases to a depth of at least 2 feet prevents the development 

 and emergence of flies. This depth may be reduced to a few inches if 

 the animals are buried before infestation. Protection of wounds 

 from flies is essential. Man, especially when subject to chronic 

 catarrh, should not sleep in the open without the protection of a fly 

 net ; hospitals should be carefully screened and wounded animals 

 should be placed in screened stalls or have the wounds treated with 

 pine tar or other repellent substance. Infestation of sheep at lambnig 

 time may be prevented to some extent by lambing as early in the spring 

 as feasible without danger from storms. Chloroform is the best destroyer 

 of larvae. Certain mixtures containing carbon bisulphide sold for 



