GEOLOGICAL SUEVEY OF THE TERRITORIES. 471 



9. Fentremites subconoideus. Meek.* 



10. Melonites A single, very tliick, hexaijonal, 



interambulacral plate, with outer 

 surface a little convex, and gran- 

 lar. 



12. Hemipronites Very small or only about one-half 



inch in diameter, with a higli 

 triangular area. 



13. Froductus About half an inch in diameter, very 



gibbous ; beak narrow, stTongly 

 incurved ; surface smooth, or 

 apparently so. 



14. Froduchis Like P. Mserialis, Hall. 



15. Froductus semireUeulatus^ Mar- 



tin, (species) Large and well developed. 



16. Froductus longispinus, Sowerby. Of usual size. 



17. BJiynclionella macra. Hall (?) 

 IS. BhyncJionella, imitata, Hall (?) 



19. Athyris Small, and like AtJi. hirsuta, Hall. 



20. Betzia Vernieuiliana, Hall 



21. Spirifer Very small, like a miniature 8. opi- 



mus, H. 



22. Spiriferina Like 8. spinosa {Spirifera spinosa, 



H.,) but smaller, and apparently 

 without spine-bases. 



23. Terebrattila turgida, Hall. 



24. Nucula Shumardii, Hall. 



25. Macrodon (?) 



26. Cypricardinalndianensis, {Cypri- 



cardella Indianensis, Hall.) 



27. Cypricardella plicata, Hall {^ 



28. CypricardellasubelUptica^ Hall (?) 



29. I\uculana nasuta {Nucula nastita, 



Hall?) 



30. Conoeardium IleeManum, Hall (?) 



31. Flatyceras One or more small species. 



32. Euomphalus Spurgenensis^ Hall. 



33. Xaticopsis Like Naticopsis Carleyi (Natica 



Carleyi, Hall.) 



34. Bellerophoii Two email, smooth species. 



35. Holopea Fragments of very small species. 



36. Fleurotomaria Very small. 



37. Cythere Very near C. carbonaria, Hall. 



38. Spirorbis ammtata, Hall. 



39. Fhillipsia Fragments of small species. 



JUFvASSIC SPECIES. 



NEAR LOWER CANON OP YELLOWSTONE RIVER. 



Names. Rem arks. 



1. An EcMnoid Mainly a cast of small species of an 



undetermined genus. 



* A very small, obconic species, much produced below the pseud-ambulacral areas, 

 "which are very short, or almost coufined to the summit, as iu Codasiei', though it is a 

 true Fentremite. 



