242 
HAROLD’S DISCUSSIONS. 
very small plate covering the region of the heart. 
Between these two extremes range all sizes of shells, 
varying with the amount of lime available. 
The snail was introduced into Lincoln County, 
Ya., many years agO. Climate and food here were 
very different, so that the new environment, it is 
claimed, changed the structure to such an extent that 
sixty-seven new species were developed. 
I^ear Black Lake are two lakes; the upper con¬ 
tained about 4 per cent of salt and the lower 25 per 
cent. The former is inhabited by the Artemia Satina^ 
a small shrimp-like crustacean, half an inch long. Its 
tail consists of two pointed lobes, and is covered with 
bristles and hairs. In the lower lake may be found 
the Artemia Milhausenii. This species has rounded 
tail lobes, and is destitute of bristles and hairs. Some 
years ago the dam broke, allowing most of the water 
in the upper lake to flow into the lower. This di¬ 
luted the water so that it was only 8 per cent salt. 
The fresh-water Salina was carried into the lower 
lake. The water gradually became more salty, and 
in three years regained its former 25 per cent of 
salt. And the Salina ? Well, it lost its bristles, and 
its tail became rounded by degrees—in short, it was 
transformed into Milhausenii. The salt had changed 
it from one species into another. Later some of the 
Milhausen species were changed into that of the 
Salina by gradually freshening 25 per cent water to 
4 per cent. 
Small brown honey-bees were taken from high 
Burgundy to the neighboring province of Bresse. 
