# CRINOIDS AND OTHER MARINE ANIMALS FROM THE BOTTOM OF THE LOWER CARBONIC SEA.

This slab is composed of five pieces found near each other in a single layer, and represents the life of the Lower Carbonic as preserved over this limited area of the sea bottom.

Lower Carbonic or Mississippic (Keokuk Formation).

CRAWFORDSVILLE, INDIANA.

Collected by D. A. BASSETT. Prepared by CHARLES SCHUCHERT.

Presented by O. C. MARSH.

Here are shown one hundred and eighteen individual crinoids belonging to sixteen species. Nearly forty forms of this class are known to occur within a few feet of strata at Crawfordsville, Indiana, whereas in existing seas it is rare to find more than a few species living together. Crinoids were the predominant element of the invertebrate life of this period in the great inland sea of the Mississippi Valley.
The numbers and letters on the fossils refer to the accompanying list of species.

## LIST OF SPECIES.

3. Barycrinus hoveyi (Hall).

6. Batocrinus indianensis (Lyon & Casseday).

17. Cyathocrinus multibrachiatus, Lyon and Casseday.

19. Dichocrinus ficus, Lyon & Casseday.

20. Dichocrinus polydactylus, Lyon & Casseday.

22. Ollacrinus tuberosus (Lyon & Casseday).

23. Onychocrinus exsculptus (Lyon & Casseday).

25. Platycrinus hemisphericus, Meek & Worthen.

27. Pachylocrinus subæqualis, Wachsmuth & Springer.

30. Pachylocrinus gurleyi (White).

31. Pachylocrinus unicus (Hall).

32. Decadocrinus depressus, Meek & Worthen.

33. Scytalocrinus grandis, Wachsmuth & Springer.

36. Scytalocrinus robustus, Hall.

37. Taxocrinus multibrachiatus, Lyon & Casseday.

41. Granatocrinus granulosus, Meek & Worthen.

46. Aganaster gregarius (Meek & Worthen).

A. Monilopora beecheri, Grabau,

F. Pugnax cfr. mutata (Hall).

G. Platyceras uncum, Meek & Worthen.

H. Platyceras equilatera, Hall.

I. Fenestella.

M. Phragmodictya catilliformis, Whitfield.