174 KAMBLES OF A NATURALIST. 



ohlcr to solve the most difficult problems of their own 

 science, they no longer turn to the oak or the palm- 

 tree for their information, but rather to the Algse 

 and the lower plants. 



In no other animals does creation exhibit itself so 

 completely in the light of a veritable Proteus as in 

 the Annelids, which are at every moment assuming 

 new forms, and surprising the observer by the mani- 

 festation of the most unexpected modifications. The 

 Polyophthalmians exhibit one of the most curious 

 examples of these metamorphoses ; but here a few 

 historical details become necessary, in order to show 

 the great interest which attaches itself to the study 

 of a small worm which is only a fraction of an inch 

 in length. 



The splendid discoveries of Ehrenberg revived in 

 1830 a discussion of originally a much more ancient 

 date. Among naturalists, some, adopting the views 

 of the illustrious Berlin microscopist, maintain that 

 even the smallest animals, those, for instance, which 

 in our scientific classifications are placed in the very 

 lowest position of the zoological scale, present an or- 

 ganisation which is fully as complicated as those of 

 the higher animals. Others, on the contrary, follow- 

 ing the steps of the celebrated founder of the Natur- 

 Philosophie, maintain with Oken that the organisation 

 is simplified in a progressive manner the lower we 

 descend in this scale ; so that entire groups, composed 

 to a certain extent of rudimentary animals, are almost 

 entirely devoid of organisation. The latter class of 

 observers agreed with Reaumur in regarding the 

 Medusae, for example, as nothing more than masses 



