NATURAL HISTORY OF CREATION, 179 



a unity in the laws wliicli brought them both into 

 existence. 



It is as yet but a few years since a system of sub- 

 ordinate analogies, not less remarkable, began to be 

 speculated upon as within the range of the animal 

 kingdom. Probably it also exists in the vegetable 

 kingdom ; but to this point no direct attention has been 

 given ; so w^e are left to infer that such is the case from 

 theoretical considerations only. We are indebted for 

 what we know of these beautiful analogies to three 

 naturalists — Macleay, Vigors, and Swainson, wdiose 

 labours have certainly involved much ingenious obser- 

 vation and reasoning, whatever we may think of some 

 of their conclusions. 



The Macleay system, as it may be called in honour of 

 its principal author, announces that, whether we take 

 the whole animal kingdom, or any definite division of it, 

 we shall find that we are examining a group of beings 

 which is capable of being arranged along a series of close 

 affinities, in a circular form — that is to say, starting 

 from any one portion of the group, when it is properly 

 arranged, we can proceed from one to another by 

 minute gradations, till at length, having run through 

 the whole, we return to the point whence we set out. 

 All natural groups of animals are, therefore, in the 

 language of Mr. Macleay, circular ; and the possibility 

 of throwing any supposed group into a circular arrange- 

 ment is held as a decisive test of its being a real or 

 natural one. It is, of course, to be understood that each 

 circle is composed of a set of inferior circles : for 

 example, a set of tribe circles composes an order ; a set 

 of order circles, again, forms a class; and so on. Of 

 each group, the component circles are invariahhj Jive in 

 number: thus, in the animal kingdom, there are five 



