414 iNOTES TO BOOK XVI. 



(R.) p. 410. I have retained in the text the remarks 

 which I ventured to make on the System of M. Agassiz ; 

 but I believe the opinion of the most philosophical ichthy- 

 ologists to be that Cuvier's System was too exclusively 

 based on the internal skeleton, as Agassiz's was on the 

 external skeleton. In s^me degree, both systems have 

 been superseded, while all that was true in each has been 

 retained. Mr. Owen, in his Lectures on Vertebrata (1846), 

 takes Cuvierian characters from the endo-skeleton, Agas- 

 sizian ones from the exo-skeleton, Linnsean ones from the 

 ventral fins, Miillerian ones from the air-bladder, and 

 combines them by the light of his own researches, with 

 the view of forming a system more truly natural than any 

 preceding one. 



(s ) p. 410. For the more recent progress of Sys- 

 tematic Zoology, see in the Reports of the British Associa- 

 tion, in 1834, Mr. L. Jenyns's Report on the Recent Pro- 

 gress and Present State of Zoology, and in 1844, Mr. Strick- 

 land's Report on the Recent Progress and Present State of 

 Ornithology. In these Reports, the questions of the Cir- 

 cular Arrangement, the Quinary System, and the relation 

 of Analogy and Affinity are discussed. 



As I have said in the text, naturalists, in their pro- 

 gress towards a Natural System, are guided by physiolo- 

 gical relations, latently in Botany, but conspicuously in 

 Zoology. From the epoch of Cuvier's Regne Animal, the 

 progress of Systematic Zoology is inseparably dependent 

 on the progress of Comparative Anatomy. Hence I have 

 placed Cuvier's Classification of animal forms in the next 

 Book, which treats of Physiology. 



