D44 DR. CARUS ON THE KINGDOMS OF NATURE, 
nal respiratory organs or gills (nearly as in the Clio* and the Cleodora); 
or lastly, we may see that the germ y grows opposite to the mouth, at 
the hinder extremity of the body, as the generator of a new interno- 
dium, that is (in the plant) as the producer of a new whole, or the or- 
gan of the plant’s propagation; and we are thereby enabled to account 
for the usual place assigned by nature to the organs of generation. In 
this way we shall always recognise that which has hitherto escaped the 
attention of the observer, namely, the analogy that exists between the 
body of the animal and that of the plant as above metamorphosed, as 
well as the manifest derivation-of the former from the latter. 
A third consequence of the above is, that the animal being the reali- 
zation of the abstract idea of unity, in which all parts must relate to a 
common centre, the sphere must be of necessity the original type of 
animal organization, the globe being that which tends to its centre 
with perfectly equal relations (radii). But, so far as the animal 
is not merely the upper part of the plant become detached, but like- 
wise contains in itself the organs of the root, the globe must be hol- 
low, and contain within itself the intestines, which can be most clearly 
pointed out in the lower animals. Because, without taking into account 
that the Infusoria appear merely as so many living hollow globules or 
cells (see the history of the green matter of Priestley, page 232, &c.), this 
kind of structure is evident in the bladder-worm (Cysticereus), in which 
(see fig. C.) the absorbing proboscis 6 (therefore called the head) is in 
reality curved inwards into the cavity of the body a, exactly in the 
manner described in the hypothetical metamorphosis of the plant into 
an animal. Similar forms are also exhibited by the Echinus tribe; to 
which we must add, that microscopical observations show most. clearly 
that the whole of the organic mass of higher animals is composed of 
minute globuli. 
The fourth consequence is, that as unity is the characteristie peculi- 
arity of an organism, there must exist, because of the greater multi- 
plicity of its form, a bond which, while it again unites that multitude, 
exhibits that relationship to a common centre which accords with its 
organization. However, since the animal presents two sides, a higher 
one, turned toward the outer world, and peculiarly animal, and a lower 
one, turned into itself, destined for reproduction, and so far purely 
vegetative, the above bond must likewise of necessity be twofold, and 
-bear a particular relation to each side. 
Fifth consequence.—No reciprocal action can take place iiebieeian 
_two bodies, except in two directions, (just as the organism itself appears 
-essentially as body and life under two forms only), namely, in its ten- 
-dency to produce a change and combination of particles,-or to a reci- 
-procal transmission of power. Inasmuch as in the animal the change 
* Carus, Lehrbuch der Zootomie, p. 482. 
