On the Siluriaii Basin of Middle Tennessee. 



355 



/ 



2. 



aUi. 



" ? n. sp. 



3. Trmnatopora, two new species. 



4. Stictopora !! four or five n. sp's. 



5. RetepQva fenestratay HalL 



6. Escharopora, n. sp. 



7. Graptolithas ample xicaulis, HalL 



8. Schizocrinus, n. sp. 



9. Fragment of a Cystidian, new genus. 



10. 



of a Sphaeronites, n. sp. 



11. Stems of Cystidi.T. 



12, Leptsena incrassata, Hall !! 



sericea, Sowerby. 

 filitexta. Hall, 

 three sps. new and undeter. 



16. OrlMs defiecta, Conrad!!* 



suhcequata, " !! 

 perveta^ " 

 tricenaria, " f 

 bellarugosa. 



13. 



14. 

 15. 



30. " lentindariSj Sowerby, 



31. Suhulites dongata^ Couradl 



32. Holopea, n. sp. 



33. " allied to obliqua. 



34. lluichisonla bicincta, Hall ! 



35. Ci/riolites compresms, Conrad. 



36. Bucania bidorsata, HalL 



37. " expansaj " 



38. Carinaropsis, n. sp. 



39. Endoceras proteitbrme, Hall I 



40. " n. sp. 



41. Orthoceras fusiforme, Hall! 



42. 



43. 



U 



ii 



ii 



17. 



18, 



19. 

 20. 



21. " sp. ? allied to disparalis. 



22. Atrypa mcrebcscens ? 



<h' a ** ^P* ' allied to recurvirostra. 

 ^4. Anibonychia amygdalina, Hall. 



of" ET " ohtusa, HalL 



^6. Edmondia vcntricosa, Hall. 



27. Madurea magna, Lesueur. 



28. Pleurotomaria umbilicata, Hall ! 



12. (c.) Upp 



multicameratum ? HalL 

 undulostriatum ? " 



44. Actinoceras tenuifilum, Halll 



45. Gonioceras auceps. Hall. 



46. Oncoceras constrictum, Hall! 



47. Lituites, 2 n. sp^. 



48. Cyrtoceras, allied to arcuatum, Hall. 



49. Cytherinafabidites, Conrad Illf 



50. Ceraaras pleurexanthemus, Green. 



51. Calymene Blumenbachii, ** 



52. Ulsenus ovatus, Conrad. 



b^, " sp.? 



54. Phacops callicephalus, Hall. 



55. I?otelus raegistos. 



56. Tail of Lichas. 



The limestone last men- 



tjoned passes gradually into a heavy member of grayish, some- 

 tinies browm'shj blue thick-bedded layers. Such is their charac- 

 ter for the most part; within fifteen or twenty feet of the top, 

 however, the layers become thin-bedded; interstratified occasion- 

 ally vvith seams — rarely beds — of clay. The entire thickness is 

 from one hundred and ten to one hundred and thirty feet. 

 ^ This member runs in an irregular belt around the last, enclos- 

 ^"g the inferior rocks and disappearing without, beneath the sue- 

 ceedmg group. It forms, in addition, within the bell, the bases of 

 two broken lines of ridges and hills — respectively the water-sheds 

 of Stones River and the Cumberland, and of Stones and Harp- 

 ^th on the north and Duck River on the south— thus cutting off 

 the minor basin of Lebanon, and, east of Columbia, that of the 

 Duck River. 

 . 'The middle portion of the member is every where character- 



profi 



lidfied 



ijil 



.* P- deflecta has been described by ^Ir. Conrad, from an imperfect Wisconsin 

 . ?P^<^*nien,_ as Strophomena deflecta, and the same individual is figured in 'Sew York 



4 ^"^^" ^' ^^der Leptsena ; it is howeTer a true Orthis. 



T <^ytherina fabulites» eo far as I know, has never been figured ; having seen Mr. 



Conrad s original specimen I can have no doubt as to its identity with mine. 



