prefacp: to the first edition. xix 



In some parts, one of the species, by means of synonyraes, is made to 

 represent, under a single name, a great number, whicli are so different 

 from each other as to be incapable of being placed in the same genus ; in 

 others, a single species is doubled, and trebled, and appears again and 

 again successively in divers subgenera, genera, and even sometimes in 

 various orders. 



What shall we say, for instance, of the Trichechus Manatus of Gmelin, 

 which in one single specific name comprises three species and two ge- 

 nera; two genera, differing in almost every thing! By what name shall 

 we speak of the Velella, which figures there twice among the Medusae, 

 and once among the Holothuriae? How are we to bring together the 

 Biphorae; some of which are called there Dagysse, the greater number 

 Salp«, and several placed among the Holothurise? 



Thus, then, in order completely to attain the object, it was not sufficient 

 to review the species — it was necessary to review even their synonymes, 

 or, in other words, it was indispensable to reconstruct the system of 

 animals. 



Such an enterprise, from the prodigious development of the science in 

 late years, could not have been executed completely by any one individual, 

 even supposing him to have no other employment, and to live the longest 

 possible term of years. Had I been constrained to depend upon myself 

 alone, 1 should not have been able to prepare even the simple sketch I 

 now give ; but the resources of my position seemed to me to supply what 

 I wanted both of time and talent. Living in the midst of so many able 

 naturalists — drawing from their works as fast as they appeared — enjoying 

 the use of their collections as freely as themselves — and having formed a 

 very considerable one myself especially appropriated to my object, a great 

 portion of my labour consisted merely in the employment of so many rich 

 materials. It was not possible, for instance, that much remained for me 

 to do on shells studied by M. de Lamarck, or on quadrupeds described by 

 INI. Geoffroy. The numerous and new affinities observed by M. de 

 Lacepede were so many traits for my system of fishes. Among so many 

 beautiful birds, collected from all parts of the world, M. Le Vaillant per- 

 ceived details of organization, which I immediately adapted to my plan. 

 My own researches, employed and multiplied by other naturalists, yielded 

 those fruits to me which, in my hands alone, they would not all have 

 produced. Thus, by examining, in the cabinet I have formed, the anato- 

 mical preparations on which I designed to found my division of reptiles. 

 M. de Blainville and M. Oppel anticipated (and perhaps better than I 

 could have done) results of which as yet 1 had but a glimpse, &c. &c. 



These reflections encouraged me; and I resolved on prefixing to my 

 Treatise on Comparative Anatomy, a sort of abridged systematic table 

 c 2 



