C. L. Walton 
211 
portion of mountain, unless movfed by the shepherd, and this applies 
particularly to the ewes and lambs. The number of dogs kept on 
the upland farms and sheep walks is often very considerable, and 
while one or two suffice for a lowland farm, six to ten are kept in the 
uplands. It stands to reason that the vicinity of the house and buildings 
or sheep pens will be much more fouled than is the case in the lowlands. 
Further, at such times as washing, shearing etc. the number of dogs 
brought together is often very large, and infected dogs may thus spread 
the disease in a number of places. The rainfall in the uplands is also 
much heavier than in the lowlands. It is my belief that infection takes 
place largely when the sheep have been gathered together about the 
house, the washing or dipping pens etc. especially after heavy rain or 
a wet period. This is supported by the number of pet lambs that 
contract gid, a matter of general knowledge. Many sheep-men state 
that gid is most in evidence after wet years. Gid in cattle seems largely 
to be confined to the sheep walks, where the beasts chiefly graze the 
limited area of improved land, usually near the house (though in summer 
they may range more widely). 
Several men who kept stationary flocks free from gid and have 
subsequently taken mountain walks, have at once become troubled with 
the disease. There is often considerable irregularity in the number of 
cases occurring on any given holding in different years, and this may 
be influenced by the relatively wet or dry weather; but it is also affected 
by the number of young sheep, which varies considerably according to 
the weather experience during the lambing season. Adverse conditions 
may occasion heavy mortality, especially among flocks lambed at the 
higher elevations ; other causes being equal, this would affect the number 
of cases in the following year. Cases have been reported to me from 
January to June, and in the latter month in 1916 one small flock lost 
two pet lambs from this cause. The majority of cases, however, are 
noted in March and April. A mountain farmer informs me that when 
he took over his present holding (the flocks are usually transferred with 
the tenancy) 16 years ago, no less than 40 cases of Gid occurred within 
the first twelve months. The precautionary measure of destroying all 
infected heads was adopted and the total reduced to twelve within a 
couple of years; one case now and again is the present extent of the 
trouble. 
As far as treatment is concerned, extraction is commonly practised; 
many farmers own the necessary instruments and frequently operate 
for neighbours. The results vary with the operator, but on the whole 
