78 
into question. Asa Gray, in his Structural Botany , p. 1 (6th 
ed., 1882), says : “ We cannot distinguish the vegetable from 
the animal kingdom by any complete and precise definition. 
Although ordinary observation of their usual representatives 
may discern little that is common to the two, yet there are 
many simple forms of life which hardly rise high enough in 
the scale of being to rank distinctively either as plant or 
animal ; there are undoubted plants possessing faculties which 
are generally deemed characteristic of animals ; and some 
plants of the highest grade share in these endowments. But 
in general there is a marked contrast between animal and 
vegetable life, and in the part which animals and plants 
respectively play in nature. Plants only are nourished upon 
mineral matter, and upon earth and air. It is their peculiar 
office to appropriate mineral materials, and to organise them 
into a structure in which life is manifested — into a structure 
which is therefore called organic. So the material fitted for 
such structure, and of which the bodies of plants and animals 
are composed, is called organic matter. Animals appropriate 
and live upon this, but have not the power of producing it/” 
I will give another extract from Julius Sachs, Text-booh of 
Botany , p. 120, 1st ed. (translated by Bennett and Dyer). 
After observing that it is an unquestionable fact that most 
plants which contain chlorophyll obtain the entire quantity 
of their carbon by decomposition of atmospheric carbon 
dioxide, and require for their nutrition no other compound of 
carbon from without, he goes on to say : — “ Even the food of 
Fungi, which are parasitic in and on animals and plants, is 
derived from the products of assimilation of plants containing 
chlorophyll, inasmuch as the whole animal kingdom is de- 
pendent on them for its nutrition. The compound of carbon 
originally present on the earth is the dioxide, and the only 
abundantly active cause of its decomposition and of the com- 
bination of carbon with the elements of water is the cell 
containing chlorophyll. Hence all compounds of carbon of 
this kind, whether found in animals, or in plants, or in the pro- 
ducts of their decomposition, are derived indirectly from the 
organs of plants which contain chlorophyll.” 
Let us now hear Dr. Carpenter, The Microscope (2nd ed., 
p. 433) : “ A more positive and easily-defined distinction 
(i.e. between Animals and Plants) lies in the nature of the 
aliment of the Protophyta and Protozoa respectively, and in 
the method of its introduction. For, whilst the Protophyte 
obtains the materials of its nutrition from the air and moisture 
that surround it, and possesses the power of detaching oxygen, 
hydrogen, carbon, and nitrogen from their previous binary com- 
