shall certainly not feel myself compelled to make 

 any such restitution. The day of publication can 

 alone decide a question of this kind, else a natu- 

 rahst might describe fifty species at random, read 

 them at a meeting of some scientific institution, 

 and then cull out at his leisure a half dozen new 

 ones, and claim them as his own six years after- 

 wards, although perhaps they had been published 

 under other names, five years before his descriptions 

 appeared. Other reasons could be given, but it is 

 unnecessary to multiply them in so plain a case. I 

 will, however, observe, that a naturalist lately read 

 descriptions of two hundred new species, and ^viien 

 his descriptions were pubhshed, they amounted to 

 tiiJO hundred and fifty— \\o\\ can any one distinguish 

 the interpolations? 



The great variety and beauty of the fresh water 

 shells of this country are truly surprising. Whilst 

 the streams of Europe contain very few species, not 

 remarkable for elegance of colour or variety of form, 

 the rivers of Ohio, Kentucky, Tennessee, Alabama. 

 &C. contain at least one hundred species of almost 

 every imaginable shape. Many of these are richly 

 coloured and ornamented with rays, tubercles and 

 undulations, and some equal in lustre the habitation 

 of the oriental pearl. To these beautiliil and muhi- 

 form shells, the few less ornamental species of tho 



osi 



