306 DIPTERA. 
often necessary in the sterile soil and 
capricious climate of Lapland. 
Lucy, But, mamma, how can they 
have milk in winter in such a country, 
when it is scarce even in England r 
Mother, In the beginning of winter 
the milk is exposed, in large shallow 
pans, to the influence of the frost ; and 
when thoroughly frozen into cakes, it 
keeps perfectly well during the cold 
months : when used, a piece is broken 
oflf and melted, and being exceedingly 
rich, it bears to be mixed with a large 
proportion of water. In Von Buck's 
Travels, you will find a very entertain- 
ing account of the w^hole process ; at 
present, as I cannot afford you more 
time, we will finish our conversation 
with the description of the ^enus oestrus. 
Antennae taper, each proceeding from a 
small protuberance — the mouth only 
a simple orifice — palpi two — and stem- 
mata three. The species cestrus bovis 
is thus described : thorax yellow, with 
four short lines — abdomen tavvnv, with 
