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the stoppage of dipping- at short intervals. Striking results are 

 reported where short interval dipping has been carried out in 

 infected areas, surrounded on all sides by farms which have been 

 infected for some years. Farms adjoining native locations, 

 where practically all beasts had died out, never had any out- 

 breaks, although cattle were dying along the dividing fence. 

 Confidence in the value of tiie dipping tank is rapidly spreading 

 and the author has no doubt that systematic short interval dip- 

 ping can effectually check and finally eradicate East Coast Fever. 

 The effect of dipping on the ticks, as reported by the farmers, 

 varies, some saying that a few days after starting the short 

 interval dipping a decrease is noticed in the number of ticks on 

 the dipped animals, and others reporting that the decrease only 

 became evident after a number of dippings or only after several 

 months. A reduction to a minimum only occurred after periods 

 varying up to 1 or even 2 years. The decrease was stated to be 

 most marked on the dewlap and udder, and between the hind 

 legs, whereas the ticks persisted longer on the eyelids, in the 

 ears and under the tail. Tlie first species to be eradicated as a 

 result of dipping is the .so-called " blue tick "* (BoopJiilvM 

 decolo/atus), which disappears after a few months. These ticks 

 pass their cycle from larva to adult on one and the same host and 

 live in the larval stage on grass for about 7 months, so that 

 within that time, provided all are reached by the dip, they must 

 completely disappear. The next said to disappear is the " bont 

 or tortoiseshell tick." which is however not found in all parts of 

 Natal, but usually on the low veld and on some farms in the 

 middle veld. Some farmers say that this is one of the hardest 

 ticks to kill and only disappears very long after dipping has 

 been adopted. This statement can be understood, because this 

 species, AinhJijonmui Jiehraeinn, requires long periods between 

 its moulting processes, so that stragglers may be caught only at 

 a very late period, long after dipping started. The disappearance 

 of the brown ticks (East Coast Fever ticks) is stated to take some 

 time, and though they are but rarely met with on the body they 

 seem to persist on various parts of the head. The life-history of 

 these ticks explains the failure of long interval dipping to check 

 them. In summer they can live in the grass for over a year, so 

 that even dipping at intervals of 5 days allows a certain number 

 of larvae and nymphs to escape, only to be caught again in their 

 adult stage, when they remain on the beast for a longer time. 

 The last tick to disappear, and all the farmers agree on this point. 

 is the red-legged tick iBhipicepludiis ererfxi), which attaches 

 itself in a well protected region under the tail. This is however 

 not the only reason for its longevity, for in the nymphal stage 

 it lives deep in the meatus of the ear and probably no liquid 

 reaches it, iior will hand-dressing suffice to destroy it. This tick 

 attaches itself chiefly to horses, sheep and goats. 



As to the possibility of stamping out ticks on a farm, evidence 



* [This popular name is a very unfortunate one, not only because it is 

 misleading in itself, but also because the term is so generally applied by farmers 

 to the inflated females of any species of tick, on account of their bluish grey 

 colouring. — Ed.] 



