248 



TRANSACTIONS OF THE 



ON THE ORGANIC REMAINS WHICH CHARACTERIZE THE 

 TRANSITION SERIES OF THE VALLEY OF THE MISSISSIPPI, 

 &c. By G. Troost, M. U. In a letter to Dr Harlan of Philadelphia. 

 [Extracted from his manuscript Report to the Legislature of Tennessee as 

 Geologist of the State.] 



I WILL commence with a list of the fossils which I 

 found in the transition strata, including the mountain 

 limestone of the English geologists. I must do so, be- 

 cause, in a zoological point of view, our carboniferous 

 limestone is characterized by the same organic re- 

 mains which in Europe are found in the grauwacke 

 group — and our grauwacke is without fossils, except a 

 few of the upper strata. The lowest fossil that I have 

 found, is the Maclurites bicarinata, Lesueur. They 

 occur in a stratum of black limestone near the Holston 

 river ; they are abundant near Kingsport, where they 

 are associated with the Conotubularia Cuvieri. The 

 next fossils are some Encrenites and Polypiferes, which 

 are so much incorporated with the rock, that I was not 

 able to distinguish them. The next series is the carbo- 

 niferous, which I considered distinct from the coal mea- 

 sures. The lowest strata are characterized by a genus 

 which I have christened Conotubularia, and we have C. 

 Cuvierii, C. Brongniardii, C. Goldfussii. 



2. Several species of Orthoceratites. 



3. Isotelus planus. 4. Astrea tessellata, nobis. 5. 

 Cyathophyllum ceratites, Goldf. 6. Cyathophyllum ver- 

 miculare, Goldf. 7. Stromatopora concentrata, Goldf. 

 8. Stromatopora verrucosa, nobis. 9. Coscinopora in- 

 fundibuliformis, Goldf. 10. Catinipora mseandrina, nobis. 

 11. Calamopora maxima nobis. 12. Columnaria diver- 



