ANIMALS AND VEGETABLES. 47 
in water, and performs all its locomotive evolutions with 
considerably rapidity. The Oyster, on the other hand, in 
which a heart, bloodvessels, brain, gills, and stomach, may 
be easily observed, has one valve of its shell cemented to 
the rock, and depends on the bounty of the waves for 
all the objects of its sensation and nourishment. 
Plants are destitute of sensation, voluntary motion, and 
locomotion. They live and die in the same spot. Where 
the seed first strikes root, there the plant continues, unless | 
transported by some foreign power, and passes through the 
various stages of growth, maturity and decay. Plants 
have been found alive, even when detached from the soil ; 
but such plants possess true roots, either as organs of sup- 
port or nourishment; and only quit their first station by 
force. ‘This is frequently the case with the floating duck- 
weed, and with the fuci which form the celebrated Mar do 
Sargasso, or sea of sea-weeds, in the great ocean. 
4. Animals differ from Plants in their Nutrition —If 
we attend to the organs of nourishment in the perfect ani- 
mals, we perceive that there is an alimentary canal, situat- 
ed towards the centre of the body, and exhibiting in some 
part of its course an enlargement, termed a Stomach. As 
we descend in the scale of animal life, this tube experiences 
remarkable changesin form and position, but continues so- 
litary in each individual. When all the other vessels of 
the body cease to be conspicuous, by reason of the diminu- 
tive size of the animal under examination, this organ may 
often be perceived. Indeed, judgmg from analogy, we 
have reason to conclude, that in every individual of the 
Animal Kingdom, there is a particular cavity destined for 
the reception of the food. 
In the most perfect vegetables, on the other hand, we 
find the alimentary tubes so numerous, that we are unable 
to count them ; and in no case do we observe any common. 
