622 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
cal, paved by small, irregular pieces, interspersed with nodose larger ones. 
Orals proportionally small, as also the radial dome plates. Anal tube 
comparatively small, and apparently short. Column composed of joints 
alternating in size; the internodal joints knife-like, the nodal ones rounded 
at their margins, and slightly crenulated. A similar crenulation occurs also 
at the rim of the basals, giving it the appearance of a stem joint. 
Horizon and Locality. — Kinderhook group; Le Grand, Marshall Co., 
Iowa. | 
Lypes in the collection of Wachsmuth and Springer. 
femarks, — This species resembles Actinocrinus tenuisculptus in the style 
of ornamentation; but differs from it decidedly in the arm structure, and 
the form of the ventral disk, which is very much lower, and the anal tube 
much smaller. 
Correction. —The specimen represented by figure 3 on Plate 17, Vol. 
VII. of the Hlinois Geological Report, which was referred to this species, 
represents a good example of Cactocrinus Arnoldi. 
Cactocrinus nodobrachiatus W. and Sp. 
Plate LVIT. Figs. 1 and 2. 
1887. <Actinocrinus nodobrachiatus —W. and Sv.; Geol. Rep. Illinois (1890), Vol. VIIT., p. 165, Plate 15, 
Fig. 5, Plate 16, Fig. 10. 
: 1890. <Actinocrinus nodobrachiatus —S. A. Minter; N. Amer. Geol. and Paleont., p. 219. 
Specimens buff colored with brownish tint. Dorsal cup inverted bell- 
shaped, the sides moderately convex, abruptly spreading below the arm 
bases. Plates decidedly convex, deeply pitted at. their angles, and covered 
with radiating ridges, which, though moderately well defined near the edges 
of the plates, are in the central portions either obsolete or become indistinct, 
even in well preserved specimens, and appear as if they had been worn off 
by attrition. 
Basals short, expanding into a conspicuous rim with a sharp edge, which 
projects beyond the limits of the column; interbasal sutures deeply notched, 
giving to the base a tripartite outline. Radials and costals decreasing in 
size upwards, the former as long as wide, the latter wider than long. First 
costals hexangular, sometimes pentangular, or even quadrangular when not 
in contact at any side with the interbrachials of the second range; the 
second costals almost twice as wide as high. Distichals one, smaller than 
the costal axillaries. Palmars one, small, the two inner ones axillary and 
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Bsa 
