42 PHILOSOPHY CF ZOOLOGY. 
By the aid of this chemical character, the aponge and co- 
ral, the only beings which make any thing like an ap- 
proach to the vegetable tribes, may be demonstrated to agree 
with the other members of the animal kingdom, in the ge- 
latine or albumen of their soft parts, and the earthy salts 
which constitute their coverings or support. 
2. Animals differ from Plants in Structure-—When 
we examine the structure of the solid parts of vegetables, we 
find them consisting of fibres or threads, which he parallel 
to one another. In the solid parts of animals, on the other 
hand, the earthy salts are arranged in plates, forming 
cells. 
Each fibre of a plant constitutes a tube or vessel for the 
circulation of the sap. As far as observation goes, these 
tubes are cylindrical throughout. They are aggregated 
into fagots, which diminish in magnitude as they proceed to 
the extremities of the plant ; but the decrease is owing to the 
separation of fibres to form smaller fagots, not by the subdi- 
vision of the tubes themselves. The vessels of animals differ 
widely from such an arrangement. ‘They do not constitute 
the solid parts. They are all of them conical, give off 
branches, and diminish by subdivision. The solid parts, 
then, of animals, are cellular ;—those of vegetables vascu- 
lar ;—the vessels of plants are parallel and cylindrical ; 
those of animals are irregular and conical. ‘The former are 
simple; the latter are branched. The organs of support in 
plants consist of the vessels themselves; in animals, they are 
chiefly secreted salts. 
3. Animals differ from Plants in thetr Action—The 
preceding observations on the composition and structure of 
organized beings, establish the existence of characters suf- 
ficiently marked to warrant the conclusion, that animals 
and vegetables belong to different systems; that there is 
a model peculiar to each ; and that, by attending to the ap- 
