INTRODUCTORY LETTER. 3 



ceptation ; it also signifies the total impression which the 

 whole of any being makes on us, — an impression which we 

 may feel, but which it is impossible to express in words : 

 it is the result of the harmony of all the isolated parts, and 

 their mutual relations, which is comprehended at a glance. 

 We retain it as a whole, without being able to give an ac- 

 count of the properties of each of them taken singly. All 

 the existences of Nature, be they animals, plants, or even 

 inanimate objects, make on us this impression ; but it is 

 the more difficult to be analyzed, as the beings we examine 

 are more complicated, for the more their nature is elevated, 

 the more do the different characters lose themselves in the 

 harmony of the whole. One of the most essential points 

 of the mark at which the zoologist aims, appears to me to 

 analyze this harmony, and to indicate each characteristic 

 trait in relation to the whole. Yet, our modern methods 

 conduct us in a path precisely opposed to that which I 

 point out. The example of the illustrious author of the 

 Systema Natur(je^ falsely interpreted, has even sanctioned 

 the practice of circumscribing the knowledge of beings in 

 general, to such characteristics as are obvious on the first 

 aspect. 



In examining a series of living animals, the attentive 

 observer A^ill remark, that, in their features, in their looks, 

 and even in their forms, he may trace the expression of 

 certain dispositions, habits, and passions, which are still 

 more directly than in man the result of organization. 

 On reiterating his observations, he will not fail to recognise 

 by their features the different species of animals ; he will 

 seize the relations which link the species to each other ; he 

 will bring them together, and in this synthetic process, 

 he %vill arrive at a natural method. A series of beings 

 thus grouped, will produce an impression of the whole si- 

 milar to what he would receive from a single individual, 

 —an impression which it is necessary to depict as a whole, 

 to obtain a knowledge of its principal features. 



This manner of examining nature is, indeed, diametri- 

 cally opposed to that wiiich sets out to distinguish indi- 

 viduals from some isolated characters ; but, as it offers the 

 only means of tracing a faithful picture of nature, as it sets 



