512 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
Horizon and Locality. — Lower Burlington limestone; Burlington, Iowa, 
and southern Missouri. 
Type in the (Worthen) Illinois State collection. 
Agaricocrinus fiscellus (Hatt). 
Plate XXX VIII. Figs. 3a, b, ¢. 
1861. Actinocrinus fiscellus — Hat; Boston Journ. Nat. Hist., Vol. VIL., p. 272. 
1881. Agaricocrinus fiscellus W. and Sr.; Revision Paleocr., Part IL, p. 112. 
Of the same size as A. brevis, and so closely resembling it that it 1s ques- 
tionable whether it is not a mere variety of that species. It differs somewhat 
in the proportions of the calyx, the dorsal cup being comparatively higher, 
and the tegmen shorter. It is also more distinctly pentalobate, the inter- 
radial depressions at the arm bases being deeper. In the ornamentation of 
the plates the two species are similar, if not identical. In the form under 
consideration, the plates to the top of the radials are horizontal, and those 
above curved abruptly upwards, with little increase in the width of the calyx. 
The basals form a hexagon with a shallow depression in the centre for the 
reception of the column, leaving the outer margins of the basal disk exposed. 
Radials wider than long, the upper part a little nodose, but without ornamen- 
tation. There are two distichals in both divisions of the three anterior rays, 
and also in one of the divisions of the two posterior ones; while the divisions 
next to the anal side have but one, which is axillary, and supports at each 
side a short palmar, making three arms to these rays against two in the 
others. The arm facets are smaller than in A. brevis; the arms not quite 
so heavy, but apparently a little longer. Tegmen very short, depressed 
hemispherical; the posterior oral large and sharply conical; the other plates 
slightly convex. The anal area is formed as in the preceding species, but 
is somewhat more bulging. 
Horizon and Locality. — Same as last. + 
Type in the University Museum at Ann Arbor, Mich. 
Agaricocrinus pyramidatus (Watt). 
Plate XXX VITT. Figs. 4a, b, c, and da, b, e. 
1858. <Actinocrinus pyramidatus — Hatt; Geol. Rep. Iowa, Vol. I., Part IT., p. 565. 
1881. <Agaricocrinus pyramidatus —W. and Sp.; Revision Paleocr., p. 112; and 1893, Whitfield, Mem. 
Amer. Mus. Nat. Hist., Vol. I., p. 23, Plate 2, Figs. 23 and 25. 
Syn. Agaricocrinus corrugatus Haut; 1861; Prelim. Deser. New Paleoz. Foss., p. 4, and Boston 
Journ. Nat. Hist., p. 283. 
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