204< SANITARY ENTOMOLOGY 



struction of ticks and mange mites on animals is important. Care 

 should be taken to guard against extensive saddle or harness sores on 

 army animals. 



Methods of preventing blowing of* wool on sheep hardly need to be 

 discussed fully here. Shearing early in the spring, avoiding the soiling 

 of wool, raising hornless breeds and the crutching, that is clipping the 

 wool at the vent and behind the hind legs greatly reduces infestation. 



Treatment of Infestations in Man. — Nasal myiasis is the most dif- 

 ficult to handle. The larvae should be removed mechanically as far as 

 possible. A number of different treatments have been resorted to, the 

 administration of chloroform into the nose being the most used. After 

 all larvaj have been taken away, it is usually necessary to exercise care to 

 prevent breaking of blood vessels which are frequently greatly exposed 

 by destruction of the surrounding flesh. In most wounds the larva are 

 quite easily removed. Of course the details of the care of the patient 

 are to be determined by the physician in charge. 



Treatment of Wovmds in Animals. — Chloroform Is the most generally 

 used of all reagents and is usually satisfactory. The chloroform is 

 poured directly into the holes and the wounds closed up. This benumbs 

 the larvae so that they can be taken out with a forceps. Carbon tetra- 

 chloride is also satisfactory for this use and considerably cheaper. 

 After the larvffi have been taken out antiseptic astringent dressing should 

 be applied and pine tar or pine oil and vaseline applied to the outside 

 to repel flies. Oil of camphor is an excellent fly repellent and aids in the 

 healing process. Bleeding wounds should be dusted with tannic acid 

 before applying the repellent. 



SUBDERMAL MIGRATORY SPECIES 



The reduction of the number of ox warbles in cattle is important 

 from the standpoint of the raiser as well as to lessen the chances of 

 infestation of man and horses. The most feasible method yet devised 

 consists in the squeezing out of the larvae from the backs of the animals 

 after they have formed the subcutaneous tumors. This should be done 

 at intervals of about three weeks, all animals being gone over carefully. 

 The period for beginning extraction varies according to latitude from 

 October 15 to March 1. 



The question of controlling Dermatobia hominis in tropical America, 

 and also its African analogue, Cordylohia anthropophaga, has not been 

 sufficiently worked out to make satisfactory recommendations. No doubt 

 where livestock are under control, systematic extraction will reduce the 

 number of these, both in animals and man. When humans become in- 

 fested it is usually advisable to allow the larva to become stationary and 



