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enumerated and all possible methods of transmission are discussed. 

 The prevalence of ticks in various regions and at different seasons, 

 the number of ticks in proportion to the cattle, and the influence of 

 climate are touched upon. 



Suggestions for eradication of the ticks include the burning of grass, 

 and it is pointed out that the later in the year this is undertaken 

 the greater is the number of ticks destroyed. Grass-burning alone, 

 however, will not eradicate ticks. Dipping is undoubtedly an efficient 

 means of destroying ticks, when carried out properly with a good dip. 

 The liquid must, however, reach the ticks, and it must be remembered 

 that these do not always die immediately ; females may even continue 

 to lay eggs though they do not hatch. B. decoloratus requires three to 

 four weeks to complete its life-cycle on an animal, and therefore dipping 

 must be practised every third week. Rhipicephalus cvcrtsi, on the 

 other hand, seeks its host twice, first as a larva, when it moults into 

 a nymph and remains on the host for 16 to 21 days before dropping, 

 and again as an adult, the female remaining on the host from 6 to 10 

 days. Dipping should therefore be practised at least every eighth day. 

 Hand-dressing as well as dipping is necessary in the case of this species, 

 owing to its habit of sheltering in the ear or under the tail, where it is 

 protected from the dip. The brown tick {Rhipicephalus appendiculatus) 

 seeks its host three times ; as a larva from three to five days, and 

 for the same time as a nymph, while the adult female requires 

 about a week before it drops to the ground. The best results are 

 therefore obtained if dipping is repeated every third day, and con- 

 tinued as long as the different stages can live in the grass, that is, at 

 least a year. The case of A. hebraeum is very similar, and dipping 

 should be practised at least about every four days for this species. 

 Dipping should be most regularly and energetically carried on through 

 the summer, when changes in tick-life are more rapid. The dips 

 recommended are those designed by Pitchford in Natal, as follows : — 



The method of preparation of the dip is described, and it is suggested 

 that a dip-tester or isometer is advisable in order to maintain a constant 

 strength. Cattle should be gradually accustomed to the dip by using 

 a weaker solution first, and then a stronger one. If a rapid reduction 

 of ticks to the minimum is desired, horses, goats, and sheep should 

 also be dipped. Animals that cannot be dipped should be sponged 

 and dressed at intervals, and as a supplementary measure all animals 

 should be sponged with the dipping liquid on those parts of the body 

 where the dip does not penetrate by the ordinary method. 



The method of starving ticks by keeping certain areas free from 

 animals for a definite period is described. The eradication of diseases 

 in which the animals do not act as a reservoir of the virus, namely, 

 African Coast fever and heartwater, can be accomplished by keeping 

 them for the requisite time, i.e., for African Coast fever about 18 days, 

 in a clean quarantine area ; after this the njaiiphs will have dropped 

 off to moult, and the animals should be removed to another clean area, 

 and after another 18 days to repeat the process they may be safely moved 



