MYIASIS— ITS PREVENTION AND TREATMENT 205 



then remove it througli the hole in the skin. It may be necessary to en- 

 \avge the hole to get it out more easily. In the case of the American 

 forms the bite from various bloodsucking Diptera should be prevented as 

 far as possible. Having the body well protected with clothing will also 

 probably reduce injury from both of these species. On account of the 

 probability that some of the African parasites of this class deposit eggs 

 on exposed clothing, especially if wet with perspiration, this should be 

 guarded against. 



SPECIES CAUSING INTESTINAL AND tTROGENITAI, MYIASIS 



CoNTROi, OF Truly Parasitic Species. — In Anivials. — There are 

 three principal methods of attack against the bots of horses. The de- 



FiG. 40. — Nose protection for horse against attacks of the nose fly, Oastrophihis 



haemorrhoidalis. (Dove.) 



struction of eggs will accomplish much good in the case of Gastrophilus 

 intestinalis and is applicable to some extent to G. nasalis, but apparently 

 can not be practiced in G. haemorrhoidalis . Dove has found that the 

 common practice of washing the legs of horses with kerosene oil has but 

 little beneficial effect. The creosote derivatives containing about two 

 per cent phenols destroyed the eggs readily. A miscible creosote com- 

 pound reduced with water to this strength and applied with a rag or 

 brush at the time the horses are groomed will destroy practically all 

 eggs present. Such treatment repeated weekly should accomplish almost 

 complete control. In this way horses and mules may be kept practically 

 free from infestation. Of course the grooming itself will tend to hatch 



