32 
MEMOIR OF 
which their distribution is regulated over the 
different portions of the globe.* 
It is farther to be observed, that a system mtist 
either be artificial or natural. The foregoing 
remarks relate to the formation of an artificial 
system. It may now be allowed to add a state- 
ment of what is to be understood by a natural 
system, or rather the natural system; for it is 
pleaded, that the true system of nature can be 
but one. The natural system is supposed to be 
that which will consist, when discovered and 
verified — for it is still a desideratum — of a develop- 
ment of the true scale of universal being, or that 
plan on which every object was created, and 
upon which animals and plants, by the interven- 
tion of an infinity of intermediate forms, blend 
into each other, and are finally so united as that 
it cannot be known where to draw the line of 
demarcation. This natural series of beings is 
complex , forming in its progress certain devia- 
tions which resemble a series of circles. A 
system can only be natural which attempts to 
explain the analogies or resemblances between 
the individuals or divisions of one circular series 
when they are compared with those of another 
circular series. The relationship between all 
natural objects is twofold — immediate and remote. 
The first of these is called an affinity, the second 
an analogy. Thus there is an affinity between 
the swallow and the goatsucker. These genera 
* Macgillivray. 
