TRANSACTIONS. 147+ 
culturists had also their maggot factories; and the ordinary earth 
worms could be gathered by the bushel by sending little boys to 
follow the plough. He further pointed out the necessity, in con- 
structing a pond, of providing for the food supply of the fish by 
introducing aquatic vegetation. There were thousands of acres 
of barren water in this country—lochs and moorland pieces of 
water, which contained only fish so small that they were not worth 
taking out. Many streams likewise contained no fish worth 
catching. These waters could be cultivated to a very considerable 
extent. A good many reasons had been adduced for the small 
size of the fish. One was that they were far too numerous. He 
had heard people recommend the putting of pike into the water to 
keep them down. That was the very worst thing that could be 
done. The presence of pike was one of the great difficulties in the 
way of successfully stocking some of the lochs in Kirkcudbright, 
of which there were somany. He did not believe that the trout 
were too numerous in any of these mountain sheets of water. He 
had seen fish do better when crowded in tanks than when dispersed 
more thinly. He had reared two hundred or more large fish in a 
pond 60 feet long and only 4 feet wide and 3 feet deep. It was 
not that the fish were too numerous ; but it was probably a want 
of food in these lakes. That want could easily be supplied. 
Aquatic vegetation could be introduced if it was deficient, as it 
often was in mountain streams, and shell fish or crustaceans could 
be put in—the fresh water shrimp, for example. The snails were . 
perfectly harmless to trout in all stages). The shrimps, unfortu- 
nately, preyed on the ova when they could get toit ; but he did not 
think they could do a serious amount of damage when the ova was 
naturally deposited by the fish, for the eggs were then buried deep 
in the gravel. Another reason which probably accounted to a 
great extent for the small size of the fish in many waters was the 
want of change of blood. He believed greatly in transferring fish 
from one water to another—introducing, of course, as far as pos- 
sible, really good fish. Many of our streams which are not large 
enough to contain good fish could be best utilised by making a 
succession of dams, which could be stocked really to any amount. 
A stream which did not contain any trout worth mentioning could 
in this way be made to produce simply tons of fish. 
