368 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Batocrinus icosidactylus Cassepay, 
Plate XX VII. Figs. Sa, b, ¢. 
1854. Batocrinus icosidactylus — CassEDAY ; Zeitsehr. d. Deutsch. Geol. Gesellsch., Vol. VI., p. 238, Plate 
2, Figs. 1, la-c. . 
1857. Batocrinus icosidactylus — Pictnt; Traité de Paléont., Vol. IV., p. 324, Plate 101, Fig. 6. 
1867. Actinocrinus (Batocrinus) icosidactylus — M.and W.; Geol. Rep. Illinois, Vol. V., p. 367. 
1881. Batocrinus icosidactylus — W. aud Sp.; Revision Paleocr., Part IT., p. 166. 
1885. <Actinocrinus icosidactylus —QuEnstEDT; Handb. der Petrefactenkunde (8te Auflage), Plate 77, 
1892. eta Nominee S. A. Mintzer; Adv. Sheets Geol. Rep. Indiana, p. 24, Plate 4, Figs. 1-5. 
Calyx nearly as wide as high. Dorsal cup rarely more than half the 
height of ventral disk, low saucer-shaped, with a protuberant base; plates 
heavy, slightly convex, their surface smooth or obscurely granular. 
Basal cup projecting conspicuously beyond the level of surrounding plates, 
almost circular in outline; the median part deeply depressed for the recep- 
tion of the column; central perforation subpentangular. Radials. short, 
partly hidden from view by the overhanging rim of the basals. First costals 
quadrangular, three times as wide as long, narrower than the second.  Disti- 
chals two, a little larger than the costals. Palmars three, increasing in width 
upward and placed in longitudinal series, which are separated by well defined 
grooves. Arm openings facing laterally, forming a continuous row around 
the calyx. Arms four to each ray; their structure not known. Inter- 
brachials three (rarely four) to the interradius; the first much larger than 
the other two. The anal plate, which resembles the radials, is followed by 
three plates, and these by one or two. Interbrachials not connected with 
the plates of the tegmen, the higher brachials being in lateral contact. 
Ventral disk conical, passing gradually into a strong, almost central tube. 
The larger plates, as a rule, are extended into thorn-like projections, and 
are surrounded by smaller, slightly convex pieces. Orals quite excentric, 
four of them spinous, the posterior one merely convex. ‘The radial dome 
plates, which are represented by plates of a first, second and third order, 
are also spiniferous. Anal tube long, heavy, and composed of convex pieces, 
among which larger thorn-like plates are scattered at intervals. Column 
round. 
Horizon and Locahty.— Warsaw limestone; Spergen Hills, Ind., and 
Barren Co., Ky. 
| 
