406 THE MANAGEMENT AND FEEDING OF CATTLE 



tar products, corrosi\'e sublimate and gray hellebore. 

 The coal tar products include some of the proprietary 

 dips. The corrosive sublimate treatment is prepared by 

 adding 15 grains of corrosive sublimate to i pint of 

 water. The gray hellebore is dusted into the hair over 

 the parts infested after the hair has been raised by brush- 

 ing it in the opposite direction from which it naturally 

 lies. A perforated box is used as a duster. Persian 

 insect powder is probably more efficacious, but is more 

 costly. A little kerosene applied occasionally with a 

 bristle brush as a spray, and, with caution, is efficacious, 

 but freely applied would remove the hair. 



As the nits hatch out in from five to ten days, a 

 second treatment should be given at an interval of a 

 week, and, in some instances, a third at a similar inter- 

 val. A complete deliverance, however, is not likely to 

 be attained unless measures are taken at the time of the 

 first application of the remedy to clean the stables. This 

 may be done by whitewashing them after the litter has 

 been removed and burned or carted quite away, or by 

 spraying them thoroughly with a 3 per cent solution of 

 carbolic acid and water or with some reliable proprietary 

 dip. 



Flies on cattle. — In the United States and Canada, 

 two classes of flies afflict cattle more or less during the 

 warm months of the year. These are known as the com- 

 mon fly (Miisca domcstica) and the horn fl}' ( Harinatobia 

 serrata). The former has doubtless been present from 

 the earliest colonization period, if not, indeed, earlier. 

 The latter was introduced from Europe about 1885. Its 

 distribution is already continental. The appearance of 

 the house fly is too well known to call for any descrip- 

 tion. The horn fly is not more than about half the size 

 of the house fly. Flies of the species frequently con- 

 gregate in great numbers when resting at or near the 

 base of the horn, hence the name. 



