﻿JOURNAL 



OP THE 



ACADEMY OF NATURAL SCIENCES 



OF PHILADELPHIA. 



Art. I. — Notice of Producti found in the Western States and Territories, with descriptions 

 of twelve New Species. By J. C. Norwood and Henry Pratten, of the Illinois 

 Geological Survey. 



The genus Productus, established by Mr. Sowerby, in 1814, being found so abun- 

 dantly in the "mountain limestone," of Europe, it was natural to suppose, that 

 when this formation, which is so extensively developed in our Western and Southern 

 States, came to be explored, it would yield many more species than it was known to 

 furnish when M. de Koninck published his admirable monograph on the Producti, in 

 1847. This expectation has, in some degree, been realized ; twelve new species being 

 now added to the published catalogues of American and European palaeontologists. 



The wide distribution of this formation in North America, occupying, as it does, 

 extensive districts in the States of Kentucky, Indiana, Illinois, Missouri, Iowa, Ten- 

 nessee, Alabama, and Arkansas, together with Nebraska territory, as well as on the 

 Humboldt river, in Utah, we may reasonably expect that the present list will be 

 greatly extended, especially when the State collections of Missouri, Illinois and Ken- 

 tucky come to be examined and collated. 



It is not, however, in the " mountain limestone " alone that the Producti are so 

 widely distributed. The marine limestones and calcareous clays of the coal measures 

 are equally, if not still more, prolific in species of this genus. Many of the species 

 in the following list are found, exclusively, in that formation ; and, with a few species 

 of other genera, are the most reliable indicators in the exploration of our Western 

 coal fields. 



vol. in. 2 



