206 LEA ON SOME NEW FOSSIL MOLLUSCS, &c. 



Pal^eoniscus? Leidyiana. Plate 20, figs. 4 and 5. 



I am induced to represent the most perfect, out of some half dozen fish scales on 

 the specimen. One of them is magnified to about four diameters. They all seem to 

 belong to the same species. The scales are diminutive, rhomboidal, serrated on one 

 edge, and marked with nearly equidistant striae, which are arrested by transverse 

 striae. I name this after my friend Joseph Leidy, M. D. 



In giving the above descriptions, I am aware of the disadvantage arising from the 

 want of perfect descriptions : but as these forms are the only ones yet found, that I 

 am acquainted with, I have deemed it better to give an exact representation of the 

 specimen itself, and to give provisional names, that geologists may be able to 

 recognize them when met with again. 



