Mr. Lambert was so good as to send the following ac- 
count of it: “ The Gillaroo Trout which I sent you was 
caught in the lake Carra, situated in the county of Mayo 
in the west of Ireland, while I resided at Castle Bourke, 
situated on the banks of that lake. I had frequent op- 
portunities of observing this singular fish, and hardly a 
day passed without my catching some of them with the 
fly, or having some of them sent me by my tenants. At 
different times I opened several of their enlarged stomachs, 
which I always found full of Helix tenlaculata. This 
enlargement of the stomach is no doubt occasioned by 
this kind of food producing a certain degree of irritation 
so as to thicken the coats of it. It is certainly not a disease, 
as the larger the stomach the fatter the fish ; and a Trout 
about two pounds weight with a stomach the size of a 
hen’s egg, was so fat and oily as scarcely to be eatable. 
This fish is easily taken with a fly, and I have caught 
several in a day with much coarser tackle than I could 
have taken the Trout with in the rivers of England. It 
is certainly not a distinct species from the common 
Trout, as some have thought it; for I have found the 
stomach in every state of enlargement from the size of 
a nut to that of a hen’s egg ; and I have as often caught 
them in the same lake without the least enlargement of the 
stomach. The shell on which they feed seems to be very 
abundant in the lake Carra, as some parts of the shores of it 
are covered with the half-digested shells voided by this fish. 
I have been informed that they are sometimes caught in 
some of the neighbouring lakes. ” 
On examining the stomach of the above specimen I 
found both Helix tenlaculata and Nerita Jluviatilis ; the 
first in the greatest abundance, but both with their oper- 
culums on, and the snail or animal very little altered; a few- 
loose operculums and empty shells were among them : 
