296 FIRST PRINCIPLES OF NATURAL CLASSIFICATION. 



similar way j particularly the American redstart (Seto- 

 phaga ruticilla) and the common domestic duck. * 



(359') Our exposition of the natural system must 

 here terminate. We have endeavoured to treat the sub- 

 ject with that simplicity and clearness suited to an ele- 

 mentary work of this nature, but we foresee that many 

 will consider it too abstruse for general application : 

 this, indeed, must be granted; for although the arrange- 

 ment of nature, as we have seen, can be reduced to the 

 most simple and universal principles, the right appli- 

 cation of these principles, amid the infinite diversity of 

 her productions, can only result from study and expe- 

 rience. A knowledge of particulars as well as of generals, 

 is equally essential to the discovery of a natural assem- 

 blage of beings, or, to speak technically, analysis and 

 synthesis must walk hand in hand. Let not the student, 

 however, be discouraged ; for although there is no royal 

 road to this or to any other science, his path, we trust, has 

 been smoothed, he is in possession of that knowledge 

 which has been the progressive growth of ages, and many 

 of the stumbling-blocks, which heretofore impeded his 

 way, are removed. Much has been done, but incalculably 

 more remains for future discovery ; new and untrodden 

 regions lie before him : let him become qualified for 

 their investigation : remembering that the boundaries of 

 science are nowhere fixed, like the pillars of Hercules, 

 nor inscribed with a ne plus ultra. 



(360.) To those who are already distinguished as 

 profound observers of nature, we shall now, in conclu- 

 sion, address a few remarks on questions of a somewhat 

 intricate nature. We have elsewhere expressed an 

 opinion f, that the doctrine of analogical representation, 

 at that period, was most imperfectly developed ; subse- 

 quent attention, nevertheless, has thrown much light 

 upon this subject. We now believe that the true analogies 

 of a group, when compared with the higher assemblages 

 of which it forms a part, can only be detected when the 

 typical division of one is placed opposite to the typical 



* Journal of the Royal Institution, new series, No. iv. p. 11. 

 f North. Zool. vol. ii. p. 199. 



