266 



FIRST PRINCIPLES OF, NATURAL CLASSIFICATION. 



their introduction in this place would have extended 

 our remarks to a volume, and have so embarrassed our 

 definitions,, that, although the adept could have under, 

 stood them, the student would have been perplexed. 

 When each class of animals, in the succeeding volumes 

 of this series, comes to be treated of separately, we 

 shall then, and then only, enter upon demonstration. 



CHAP. III. 



THE FIFTH PROPOSITION CONSIDERED. ON THE RELATIVE 



RANK OF THE DIFFERENT CIRCULAR GROUPS IN THE ANIMAL 



KINGDOM. ON SPECIES AND VARIETIES ON THE MEANS 



THUS OFFERED BV THE LAWS OF NATURAL ARRANGEMENT, 

 FOR THE VERIFICATION OF GROUPS. FAMILIAR ILLUSTRA- 

 TION OF THE PRINCIPLES OF CLASSIFICATION HERE DE- 

 VELOPED. QUESTIONS ON ANALOGICAL COMPARISONS. 



(324.) THE fifth and last proposition with which we 

 commenced this part of our volume, is as follows : 

 That the different ranks or degrees of circular groups in 

 the animal kingdom are nine, each being involved within 

 the other. The full demonstration of this law would 

 obviously require an analytical exposition of the whole 

 number of circles here mentioned ; which, to do tho- 

 roughly, would in itself require a volume. We can, 

 therefore, only offer presumptive evidence on its appa- 

 rent accuracy, drawn from facts, observations, and in- 

 ferences already before the public, and which have 

 remained unquestioned. Species and varieties will next 

 claim our attention: and, finally, we shall conclude 

 this division of our volume with a brief enumeration 

 and a familiar application of those laws by which na- 

 tural groups are to be verified. 



(325.) We have seen that the whole animal kingdom 

 is composed of an infinite number of circles, touching 



