190 Mr. H. E. 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 

 ramification. 



B--A--C--D 

 i 

 i 



E 



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 formulae 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 on a 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. 



* If 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. 



