116 Analytical Notices of Books. 



illustration. But there is yet another point of view in which these very" 

 distinct modes of regarding the productions of the creation differ also 

 most completely; the comparative facility of their promulgation. He 

 who proposes an artificial system needs only that his attention should be 

 fixed on some leading character on which to found his principal groups ; 

 on some other character by which his secondary assemblages may be 

 distinguished from each other ; on a third, a fourth, or a fifth for his minor 

 divisions; and his work is done. Uniform principles, applied throughout 

 the whole of her domain, enable him to give at once to the world a System 

 of Nature, complete in all its parts, and extending from Man downwards 

 to the Monas, to the Tremella, or to the dust. 



But the investigator who aims at following Nature in the course she 

 has herself pursued, quickly discovers that the trammels of an artificial 

 system accord not with her infinite variations; that the character, on 

 which in one department the utmost reliance is to be placed, becomes in 

 another perfectly valueless; and that the minute distinctions, which may 

 here be passed unnoticed, require elsewhere to be dwelt on with critical 

 niceness. He finds that it is requisite not only to take into consideration 

 the whole of the organisation, and combine with it as far as possible the 

 habits, of the subjects on which he is engaged, but also to endeavour to 

 detect the principles by which Nature has been guided in this particular 

 group, and to apply them to his previously obtained knowledge. By 

 these means alone can he hope to succeed in tracing correctly the con- 

 nexions and differences impressed by her hand; and even when he has 

 possessed himself of the filum Ariadneum, which may in one group be 

 followed with certainty, in another it is found to be so repeatedly broken 

 as to appear ravelled and confused. Hence the exposition of his views, 

 which, from the hmited faculties and knowledge of man, can probably 

 never become perfect, is in its very commencement the result of long- 

 continued enquiries and almost indefatigable study; its progress is neces- 

 sarily slow, and years pass away before he is enabled to sketch even a 

 satisfactory outline of a single department of Nature of moderate extent. 



If the disinclination almost universally entertained to admit readily 

 of any thing which savours of innovation, has in some measure militated 

 against the reception into general use and study of the circular system 

 propounded by Mr. W. MacLeay, to the obstacles opposed to its promul* 



