236 ESSAY ON CLASSIFICATION 



ence. Oken, Kieser, Bojanus, Spix, Huschke/^ and Carus are the 

 most eminent naturalists who applied the new philosophy to the 

 study of Zoology. But no one identified his philosophical views so 

 completely with his studies in natural history as Oken. 



Now that the current is setting so strongly against everything 

 which recalls the German physiophilosophers and their doings, and 

 it has become fashionable to speak ill of them, it is an imperative 

 duty for the impartial reviewer of the history of science to show how 

 great and how beneficial the influence of Oken has been upon the 

 progress of science in general and of Zoology in particular. It is more- 

 over easier, while borrowing his ideas, to sneer at his style and his 

 nomenclature than to discover the true meaning of what is left un- 

 explained in his mostly paradoxical, sententious, or aphoristical ex- 

 pressions; but the man who has changed the whole method of illus- 

 trating comparative Osteology — who has carefully investigated the 

 embryology of the higher animals at a time when few physiologists 

 were paying any attention to the subject, who has classified the three 

 kingdoms of nature upon principles wholly his own, who has per- 

 ceived thousands of homologies and analogies among organized be- 

 ings entirely overlooked before, who has published an extensive 

 treatise of natural history containing a condensed account of all that 

 was known at the time of its publication, who has conducted for 

 twenty-five years the most extensive and most complete periodical 

 review of the natural sciences ever published, in which every dis- 

 covery made during a quarter of a century is faithfully recorded, the 

 man who inspired every student with an ardent love for science and 

 with admiration for his teacher — that man will never be forgotten, 

 nor can the services he has rendered to science be overlooked so long 

 as thinking is connected with investigation. 



CLASSIFICATION OF OKEN 



The following diagram of Oken's classification is compiled from his Allgorieine 

 Naturgeschichte fiir alle Stmide (14 vols., Stuttgart, 1833-1843), I. 5. The changes this 

 system has undergone may be ascertained by comparing his Lehrbuch der Naturphilos- 

 ophie (3 vols., Jena, 1809-1811; 2d ed., Jena, 1831; 3rd ed., Zurich, 1843; tr., A. Tulk, 

 London, 1847); Lehrbuch der Naturgeschichte (Leipzig, 1812; 2d ed., Weimar, 1815; 3rd 

 ed., Weimar, 1825); Handbuch der Naturgeschichte zum Gebrach bei Vorlesungen (2 

 vols., Nuremberg, 1816-1820); Naturgeschichte fiir Schulen (Leipzig, 1821); and various 

 papers in Isis (Jena and Leipzig, 1817-1847). 



« [Dietrich Kieser, 1779-1862; Ludovici Bojanus, 1776-1827; Emil Huschke, 1797- 

 1858.] 



