rLANARIA GRAMINEA. 115 



leech, snight perhaps be constituted, and 

 others analogous to worms. Trivial dis- 

 tinctions, indeed, should be disregarded, 

 not only to avoid the multiplication of ge- 

 nera, which would thus be extended to in- 

 finity, but to simplify the arrangements of 

 Natural History, and render them compre- 

 hensible from prominent features. Yet to 

 include in the same class creatures provi- 

 ded with organs totally wanting in those 

 associated with them, subsisting on food of 

 opposite qualities, and living in different 

 elements, which would reciprocally be fatal 

 to their existence, certainly does seem an 

 anachronism, and is not easily reconcileable 

 to strict and logical reasoning. 



The precise place which the animal that 

 shall be here denominated planaria grami- 

 nea should occupy in the system of nature, 

 has been controverted by observers. Some 

 have called it a planaria, others a leech, 

 and in truth it perhaps participates of the 

 general characteristics of both. Therefore, 

 to shun the perplexity which the multipli- 



