552 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Keokuk group, beyond which no vestige of them has been seen. There are 
about sixty American species, and perhaps twenty from Europe, where it 
occurs also only in the Mountain Limestone. 
Fig. 19. Aetinocrinus. 
(Explanation of the letters as in Fig. 12.) 
ACTINOCRINUS J. S Mitter. 
(Restricted. ) 
1821. J. 8S. Mitier; a History of the Crinoidea, p. 94. 
1844. McCoy; Synops. Carb. Foss. Ireland, p. 181. 
1844. De Konincx; Description Anim. Foss., p. 49. 
1853. Dz Koy. and Lu Hon; Recher. Crin. Terr. Carb. Belgique, p. 123. 
1855. F. Roemer ; Letheea Geogn. (Ausg. 3), Jahre. XIX., p. 246. 
1857. Prorer; Traité de Paléont., Vol. IV., p. 323. 
1866. Mex and Wortuen; Geol. Rep. Illinois, Vol. IL., p- 147. 
1873. Murx and Wortuen; ibid., Vol. V., p. 341. 
1878. Zirrei; Handb. d. Paleontologie, Vol. I., p. 369. 
1881. W. and Sp.; Revision Paleocr., Part IL, p. 188 (Proceed. Acad. Nat. Sci. Phila., p- 312). 
1889. S. A. Miner; N. A. Geol. and Paleont., p- 216. 
Syn. Blairocrinus 8. A. Mitten; Ady. Sheets 17th Rep. Ind., p. 69. 
