190 Mr. H. EK. Strickland on the Natural System 
fact, that a species has only one direct affinity, and in other 
cases that it has three or more, showing the existence of late- 
ral ramifications instead of a simple line; as shown in this 
example, where C, besides its affinity to A and D, has an af- 
finity to a third species, E, which therefore forms a lateral 
ramitication. 
B--A--C--D 
EK 
It was the observation of this fact which led some natural- 
ists to adopt the circular instead of the linear theory, still ad- 
hering to the assumption of a symmetrical figure, but chan- 
ging their notions of its form. Now although we find occa- 
’ sional ramifications in the affinities, and although these rami- 
fications may occasionally anastomose and form a circle, yet 
it has been shown that the doctrine of a regular figure cannot 
be sustained, and therefore if even it be permitted to man to 
discover what the true figure is which will express all the af- 
finities of organic bodies, it can only be effected by construct- 
ing it piecemeal in the way above proposed. All that we 
can say at present is, that ramifications of affinities exist ; 
but whether they are so simple as to admit of being correctly 
depicted on a plane surface, or whether, as is more probable, 
they assume the form of an irregular solid, it is premature to 
decide. They may even be of so complicated a nature that 
they cannot be correctly expressed by terms of space, but are 
like those algebraical formule which are beyond the powers 
of the geometrician to depict. Without, however, going 
deeper into this obscure question, let us hope that the affini- 
ties of the natural system will not be of a higher order than 
can be expressed by a solid figure; in which case they may 
be shown with tolerable accuracy on a plain surface ; just as 
the surface of the earth, though an irregular spheroid, can be 
protracted ona map. The natural system may, perhaps, be 
most truly compared to an irregularly branching tree, or 
rather to an assemblage of detached trees and shrubs of vari- 
ous sizes and modes of growth*. And as we show the form 
of a tree by sketching it on paper, or by drawing its indivi- 
dual branches and leaves, so may the natural system be drawn 
on a map, and its several parts shown in greater detail on a 
series of maps. 
* Tf this illustration should prove to be a just one, the order of affinities 
might be shown in museums in a pleasing manner by constructing an arti- 
ficial tree, whose ramifications should correspond with those of any given 
family of birds, and by then placing on its branches a stuffed specimen of 
each genus in their true order. 
