Prof. Ehrenberg's Researches on the Infusoria. 207 

 In the year 1823, Losano described a great number of in- 

 fusoria in the Transactions of the Turin Academy, vol. xxix. 

 He has extended the genus Proteus, which Miiller only reckon- 

 ed to contain 2 species, and Schrank 4, as far as 69- And the 

 genus Kolpoda he has increased to 64 species, which was left 

 by Miiller with only 16. 

 ' The latest general classification of the infusoria is that given 

 by Bory de St Vincent in 1826, in the Dktionnaire Classique 

 de PHist. Nat. In this elaborate production, which is charac- 

 terized by the minuteness and spirit of system so prevalent 

 among his countrymen, the author has exclusively confined 

 himself to the artificial dismemberment and rej unction of the 

 species already known in the time of Miiller. He has added 

 no observations of his own on their structure or development ; 

 and bases his system, like his predecessors, on their external 

 forms. M. Bory seems not to have been aware of the observa- 

 tions of Nitsch, for in his definition of the class, he asserts them 

 to possess no trace of eyes, and that their nutrition is performed 

 by cutaneous absorption, and their propagation to be gemmipa- 

 rous ; all of which points had been previously shewn to be er- 

 roneous, notwithstanding the otherwise imperfect knowledge of 

 their organization. More profound views were entertained by 

 Professor Baer of Kbnigsberg, in 1826, who published a trea- 

 tise, entitled Beitrage zur Kevntniss der Niedern Thiere, in 

 the 2d volume of the Nova Acta Acad. Cces. Loop. Car. x. 

 p. 702, 1826-7, which contains the following remarkable pas- 

 sages . P. 337, he observes, " Who can deny that even the lowest 

 class of animals must agree with the others in being determined 

 by its organization ; since the first essential step towards the 

 organization of an animal body must consist in the separation 

 of an internal nutritive surface from an external circumscribing 

 one .? Lamarck must certainly be in error when he considers the 

 want of a digestive cavity and of a moutli the character of his 

 first class of animals." In prosecution of these simple and cor- 

 rect views, he again says : " This first class of animals, which 

 must change the term of Infusoria given to it by many for 

 Goldfuss's one of Protozoa, cannot be so circumscribed as Mlil- 

 ler's Infusoria. It appears to us rather that many fundamental 



