DISEASES DUE TO INTEENAL PARASITES. 211 



The point of choice for trephining will be in each of the two 

 upper angles thus obtained, without engaging the lines which 

 limit them. The operation is performed according to the ordin- 

 ary rules of surgery. From the opening made one often sees the 

 larvae, which are extracted by forceps. To kill others, benzine 

 moderately diluted with water is injected. The flap of skin 

 is then cleaned, applied to the opening and sewed to the adjoin- 

 ing skin. The whole is then covered with a turpentine-coated 

 leather plaster. The patient is separated for a few days froni 

 other sheep. Sheep bear the operation with the same impunity 

 as they do marking the ears or other minor operations." This 

 operation would not be advisable in the hands of every flock 

 owner, and when all is said and done, it only relieves the trouble 

 for the time being, as the next fly which comes along and de- 

 posits its larvae will create the same trouble. Perhaps the ad- 

 vice given by Xeumann, in his work on parasites, is the best and 

 easiest carried out (except where the sheep are valuable and de- 

 sired for breeding purposes). lie says: "At all times, if the 

 number of animals affected is considerable, the malady should 

 be left to follow its course, and those which present the gravest 

 symptoms should be sent to the shambles." 



As a preventive in large herds the following might be tried : 

 Take a squared log and bore holes in it with a large augur; in 

 these place salt, and dress the edges of the holes with tar. Sheep 

 then will apply tar to their noses every time they eat the salt. 



parasitic Broncbttis; Boose, Rush. 



Also vulgarly called "Snots." This destructive affection is 

 due to the invasion of the bronchial tubes and lung tissue by 

 worms scientifically called the strongylus filaria and strongylus 

 rufescens, the former, however, is the one most frequently pres- 

 ent, and is found attacking other ruminants, notably the camel 

 and goat. 



