New Publications. 401 



5. On Fossil Fishes, comprising 500 extinct s/)ecies ; an ExpotUion tf 

 the Laws of the Succession, and of the Organic Developpient of 

 Fishes, throughout all tfie revolutions of tJie terrestrial globe ; a 

 new Classification of those Animah, expressing titeir relations to 

 the series of formations ; and, lastly, tJie general geological consi- 

 derations deduced from the study of these organic remains. By 

 Dr Louis Aoassiz. In 5 vols. ; the text in 4to, and 250 plateti 

 in folio, on fine paper. 



» It is now, says Professor Agassiz, nearly three years since 1 

 announced this publication in tlie prospectus of my " Fresh- 

 water Fishes of Europe.'''' Circumstance over which I had no 

 control, have, till now, prevented the publication of these tw(j 

 works, which ought to have appeared together, for their mutual 

 completion, and for exhibiting my idea of the science of Ich- 

 thyology. A more favourable position now enables me to un- 

 dertake this enterprise,. and I commence with printing my Fossil 

 Fishes. The mere study of species, and their individual organi- 

 zation, has been almost the exclusive aim of naturalists. When 

 they have pushed their investigations farther, the objects of their 

 research has been limited to the philosophic principles of their 

 classification and organization. I have also constantly kept in view 

 these two points in my researches on fossil fishes. In establish- 

 ing successively 500 extinct species, the remains of which are 

 scattered through all the collections of Europe, I have made many 

 new observations on their structui-e, as compared with that of 

 existing fishes, and other vertebrate animals. But this study has 

 led me farther. I have deduced the law of succession and or- 

 ganic development throughout every geological epoch. In the 

 contemplation of this class, during its successive metamorphoses 

 from formation to formation, science may trace, in this one 

 grand division of the animal kingdom, the progress of organiza- 

 tion through a complete series of the different ages of the earth. 

 After such multiplied comparisons, it will not excite surprise 

 that I announce changes in the classification of fishes, which will 

 often indicate, at the same time, affinities hitherto unknown ; 

 but the most interesting circumstance is, that the new classifica- 

 tion which I am about to promulgate, will completely express 

 the natural affinities of fishes with each other, and their succes- 

 sion in the series of geological deposits. The general geologi- 

 cal principles deduced from the study of these fossil remahis^ 



VOL. XV. NO. XXX. OCTOBER 1833. C C 



