o 
THE COTTAGE GARDENER. 
[October 3. 
where animal life terminates and where vegetable life 
begins:—the zoophyte, or plant-animal, connects the 
two kingdoms. 
To determine whether plants possess a degree of sen¬ 
sitiveness is not so easy as many persons may believe. 
“It is as difficult,” says Mr. Tupper, who has written 
ably upon the subject, “to ascertain the nature of vege¬ 
table existence as to determine what constitutes the 
living principle in animals.” Darwin, by the aid of 
imaginary beings similar to the Dryads and Harmadryads 
of the classic mythology, has raised plants to a position 
in the order of nature superior to that to which animals 
are entitled. Other philosophers, taking a totally an¬ 
tagonist opinion, estimate vegetables as bodies, only 
somewhat more organised than crystals, but, like these, 
entirely and exclusively subject to chemical and me¬ 
chanical changes. 
The above opinions are equally erroneous, for it 
might easily be made to appear that the gradation from 
reason to instinct, from instinct inanimation, is as 
gradual as the transitions of light from the noontide to 
the midnight of a summer’s day; but our few remarks 
must be confined to that section of creation that com¬ 
mences from the close of the animal classes in the 
zoophyte, and terminates where inorganic matter com¬ 
mences in the crystal; and the details must be specially 
directed to demonstrate how closely it approaches, how 
distinctly it is divided from, the former. 
Let us first consider the comparative composition of 
animals and plants demonstrated by the researches of 
chemists. Their constituents are identical:—carbon, 
hydrogen, oxygen, nitrogen, sulphur, phosphorus, acids, 
alkalis, earths, and metals are the common components 
of both. Nitrogen has been considered by some chemists 
as the constituent, marking by its presence animal from 
vegetable matters; but the distinction fails, inasmuch 
as that from some animal matters it is absent; whilst 
in the gluten of plants—a chief constituent of wheat— 
in all seeds, and in the whole frame of the tobacco, it is 
present. 
If we follow the above chemical bodies through their 
combinations, we shall find that these in animals and 
plants are closely similar, and in both are equally 
numerous and intricate. 
ANIMALS. 
1. Sulphuric 
Phosphoric 
Muriatic 
Carbonic 
Benzoic 
Oxalic 
Acetic 
VEGETABLES. 
1. Sulphuric 
2. Phosphoric 
3. Muriatic 
4. Carbonic 
5. Benzoic 
6. Oxalic 
7. Acetic 
8. Malic 
8. Malic 
and others equally numerous in each, but not common 
to both. Of the earths and alkalis, lime, magnesia, 
silica, soda, and potass, are found in each class. Of the 
metals, iron and manganese are their conjoint consti¬ 
tuents. 
If we follow the two classes through their more 
compound constituents, we shall find the analogy still 
holds: they contain, in common, sugar, mucus, jelly, 
colouring, and other principles, gluten, fibrin, oils, 
resins, and extractives. 
The functions of animals and plants are similarly 
closely analogous. Animals take in their food by the 
agency of the mouth, and prepare it for digestion by 
various degrees of mastication or attrition, as in the giz¬ 
zard of birds. In this they differ from plants, but these 
have this compensation, they imbibe their food in a fluid 
form, and consequently in a state of the finest possible 
division. Animal and vegetable remains are their com¬ 
mon food, plants having this superiority over animals, 
that, as they only absorb the soluble and finer parts, they 
are not obliged to throw off the grosser constituents which 
appear in the excrement of animals, though there are 
excretions given off from every part of plants differing 
probably in every genus. In the animal stomach the 
food undergoes an extensive change, being reduced to a 
pulp of greater specific gravity, and being altered entirely 
both in taste and smell. In the lymphatics of plants, 
which may be considered their primary organ of diges¬ 
tion, their food or lymph undergoes a change precisely 
similar; its colour and flavour are altered, and its 
specific gravity increased. 
From the stomach the animal’s food passes into the 
intestines, is there subjected to the action of the bile, 
and converted into chyle, the nutritive part, and excre- 
mentitious matter. In their passage through the intes¬ 
tines the chyle is absorbed by the lacteal vessels, and is 
conveyed into the blood; by the heart, the mingled 
fluids are propelled into the lungs, to be there exposed 
to the action of the air. The vital fluid there changes 
its purple hue for a florid red, loses a portion of its 
watery particles and carbon; the latter combining with 
the oxygen of the atmospheric air in the lungs, and 
being breathed forth in the form of carbonic acid gas. 
As plants in their food take in no gross, unnecessary 
ingredients, it is obvious that no process like the biliary 
operation is required. The lymph or sap, proceeding at 
once along the branches, is poured into the leaves, the 
very lungs of plants. There, as in the blood, its colour 
is changed, oxygen is emitted from it during the light 
hours of the day; but carbonic acid gas is thrown off 
during the night, and at all periods a considerable 
quantity of water. 
From the lungs, by the agency of the heart, the blood 
is propelled through the arteries over the whole animal 
system, supplying nourishment and warmth to all the 
parts, and where, by these abstractions, being again con¬ 
verted into purple or venous blood, it is returned by the 
veins to undergo the changes that were described as 
being effected by the lungs. 
The sap, after exposure to the action of the air in the 
leaves, is returned by another set of vessels situate in 
the bark, ministering to the growth and support of the 
whole plant. 
Such is the close similarity in the digestive and circu¬ 
latory processes of the two classes; a similarity which 
obtains in all the other functions enjoyed by them in 
common. In respiration, the air inhaled through the 
