ANIMAL NATURE OF DIATOMEiE. 499 



still, admitting that we are treating absolutely of the 

 being that is regarded as an animal by the author, 

 and denominated Chlamidomonas, and that the Stygeoclo- 

 nium actually derives its origin from it, the conclusions 

 from this fact may be reduced to the following ; that the 

 germs of Siygeodonium possess motions similar to 

 animals ; that they are provided with a red spot similar 

 to the eyes of Infusoria ; that they even sometimes possess 

 a terminal cilia ; sometimes a transparent space or an 

 aperture by which they fix themselves, to vegetate ; and 

 the supposed Chlamidomonas Pulvisculus is nothing more 

 than the germ of Stygeoclonium. As to the other or- 

 ganisms, as well animal as vegetable [Tetraspora, Pal- 

 mella botryoides, Protococcus, Gyyes, Pandorina, Monas, 

 Gloeocapsa, Sfc) which seem to have an origin similar to 

 that of CJdamidomonas, Kiitzing merely intimates their 

 similarity of form. 



Our author rightly distinguishes the two methods 

 pursued in the study of organic beings ; to consider them 

 either with Linnaeus, completely developed, or with 

 Goethe, in their successive development. The definitions 

 of the former are derived from an empirical synthesis ; 

 I do not allow that such can only be arbitrary, because 

 no empirical idea can be defined ; for it appears to me 

 that we can know nothing more than we learn by our 

 senses, and therefore I rather believe all those definitions 

 to be arbitrary which are not logically empirical. The 

 history of the successive development of a being, ap- 

 proaches more nearly to the true idea that we ought to 

 form of it, not because that idea is absolute, for there 

 can be nothing in nature absolute to us who form 

 part of nature herself, but because the notion or con- 

 ception of a thing is so much the less incomplete, 

 the more numerous the points of view are from which 

 we consider it. And thus, in examining the successive 

 stages of development, we always fall into arbitrary 

 error, for time has no interruption, and in this respect 

 there is an imperfection inherent in our nature ; for we 



