MACKREL. 
170 
of Green which varies as the fish changes its po- 
sition : the bright silver colour of the abdomen, 
and the varying tinge of gold green which runs 
along the sides, are eminently beautiful in this spe- 
cies ; but are only to be seen in perfection when 
the fish is first taken from the water, as death con- 
siderably impairs the colours, though they are then 
far from being obliterated. 
Immense swarms of mackrel visit our coasts at 
particular seasons of the year ; and, after remaining 
a few months, leave us, as we are informed, to win- 
ter within the arctic circle ; where they lie, during 
the severity of the weather, imbedded in the soft 
mud, and are thus protected from the effects of 
frost. They are sometimes even partly enclosed 
by the ice, which has been seen entirely bristled 
over by the tails of mackrel, imbedded in it nearly 
three parts of their length. They were observed 
in this situation by M. Pleville-le-Peley, about the 
coasts of Hudson’s Bay, where they were found in 
the mud at the bottom of the small hollows, com- 
pletely incrusted with ice. In this torpid state 
they are said to remain till they are enlivened by 
the return of spring, and again induced to make 
their annual visits. It has been observed that their 
eyes are very dim when first they leave their re 
treats, and appear to be covered with a white film, 
which disappears about the beginning of summer, 
and leaves the fish in full perfection. 
The mackrel are supposed to pursue nearly the 
same route as the herrings, in their annual mi- 
