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direct importance for our present purpose, we do not consider it necessary 
to dwell upon them. 
The symptoms of scalding manifest themselves as follows: the skin 
becomes hot and tender and as the inflammation progresses, more or 
less induration, which in bad cases is followed by wrinkling and cracking, 
with oozing of blood and serum from the fissures, makes its appearance. 
A constitutional symptom which is almost invariably present is diarrhoea, 
and this tendency to ‘ scour, ’ which is often the first and only sign of 
scalding, is of great importance and should not escape attention. The 
maximum degree of soreness is naturally found in those parts where the 
skin is most subject to flexion, particularly the knee and the hock, and 
in consequence the animal walks stiffly and shows a great disinclination 
to movement. 
As the inflammation subsides, the cuticular layers of the skin peel 
off and as the hair follicles are not affected a new growth of hair ultimately 
appears. 
The Effect of Dipping on the Tick. 
Concerning the precise mode of operation of the dip in killing the 
tick, various views have been formulated which may be summarised 
as follows: 
(a) That the tick absorbs the poison through its own skin, either 
in the dipping bath or subsequent to the dipping. 
( b ) That the tick imbibes the poison with the blood which it sucks 
from the host. 
In order to ascertain whether it is possible for a tick to absorb a 
lethal dose of the poison through its skin, various investigators have 
submitted ticks removed from an undipped host to the action of a dipping- 
fluid. The authors made the observation some years ago that mere 
immersion of free ticks in a dipping-fluid does not kill them. Ransom 
and Graybill (1912) found that engorged female ticks generally survived 
this treatment, but many failed to lay eggs, and in those cases where 
oviposition took place, the eggs failed to hatch. In two experiments 
only, did hatching occur and then only to the extent of 1 to 2 per cent, 
respectively of the eggs laid. In practically all cases, the untreated 
ticks, used as controls, oviposited normally, and from 60 to 99 per cent, 
of the eggs hatched, while in the few cases in which the percentage 
of successful hatching was low, this result was directly attributable 
to the unfavourable conditions of humidity and temperature which 
