commencing by those which have some spinous rays, neither the 

 apodes nor subbrachians, can be classed in their suite. 



The cods, for instance, come as near as any abdominal to certain 

 acanthopterygians, and there would be no reason for placing them 

 after the abdominals, if it were to mark their rank in nature. If we speak 

 of them only in their suite, it is because the facts exposed in a book 

 can only find a place after each other. 



The same observation will apply to other fishes ; to those whose 

 superior jaw is fixed ; to those whose branchiae are in tufts ; and 

 particularly to the grand and important family of the chondroptery- 

 gians, by which we shall finish the history. 



It is in the last, particularly, that the vanity of those systems is 

 conspicuous, which tend to class beings on a single line. Many of 

 these genera, the rays and sharks for instance, are raised far above the 

 common of fishes, both by the complication of some of their organs of 

 sense, as by that of their organs of generation, which, in some of their 

 parts, are more developed even than they are in birds ; and other 

 genera, at which we arrive, by evident transitions, the lampreys, and 

 the ammocetes, on the other hand, are so simplified, that some 

 anatomists have felt authorised to regard them as the passage from 

 fishes to articulated worms : but certainly, the ammocetes, at least, 

 have no skeleton, and that all their muscular apparatus has only 

 tendinous or membranous supports. 



Let it not therefore be imagined, if we put a genus or a family 

 before another, that we consider them exactly as more perfect or 

 superior to that other in the system of beings. He, alone, could 

 entertain such a pretension, who was pursuing the chimerical project 

 of classing beings on a single line, and such a project we have long 

 since renounced. The more we advanced in the study of nature, the 

 more we were convinced that this idea was one of the most erroneous 

 that ever had obtained in natural history, the more we discovered the 

 necessity of studying each being, each group of beings in itself, and 

 in the part w^hich it plays by its properties and organization, not to 

 make abstraction of any of its relations, or any of the links which 

 connect it either to its neighbouring beings, or those which are far 

 removed from it. 



Once placed in this point of view, the difliiculties vanish, every thing 

 arranges itself spontaneously for the naturalist. Our systematic 

 methods, only taken in the nearest points of relation ; they will only 

 place one being between two others, and they are incessantly at fault ; 

 the true method sees each creature in the midst of all others ; it shows 

 all the irradiations by which it is connected more or less closely in 

 this immense net-work, which constitutes organized nature ; and 

 it is this method alone that gives us those lofty and true ideas 

 worthy at once of nature and of God ; but ten and twenty would often 

 be insufficient to express these innumerable relations. 



We warn our reader, therefore, once for all, that it is in our 

 descriptions themselves that he must look for the idea he should form 

 of the degrees of organization, and by no means in the place which 

 we shall have to assign to species ; and, nevertheless, we are far 

 from thinking tliat relations do not exist ; that no classification is 



