224 
SMITHSONIAN INSTITUTION 
PLATE 26 
(Figures natural size unless otherwise stated) page 
Mysticocrinus wilsoni Springer 84 
Figs. la-f. Seven enlarged photographic views of the type specimen, with the very short arms pre- 
served in 3 rays folding closely over the tegmen, showing the acuminate anal plate 
and the arrow-head processes between the arm-bases: i, left anterior; la, left pos- 
terior; ib, posterior; ic, right posterior, showing the radianal; id, anterior; le, 
dorsal, showing the 3 BB ; if, ventral, showing infolding of the arms. All X 4 
ig. Diagram showing distribution of all the plates; missing brachials indicated by diagonal 
hachure. 
Laurel limestone; St. Paul, Indiana. 
Thalamocrinus ovatus Miller and Gurley 13 1 
Figs.2, 2a,2&. Posterior, dorsal and ventral views of large specimen; large IBB, RA in oblique 
position, anal x in line with RR, small column-facet, and ventral cavity. 
3, 3a, 4. Ant. iR and ventral views of similar specimen, and ant. R view of another more elongate. 
5. Specimen with long arms and extremely slender elongate brachials, displaced. 
Beech River formation; Decatur County, Tennessee. 
Thalamocrinus cylindricus Miller and Gurley 132 
Fig. 6. Post, view of unusually large specimen. 
7, 7a, 7b. R. post., basal and ventral views of a typical specimen, with RR, anal and radianal 
plates in place. 
8, 8a. R. post, and ventral views of short specimen. 
9, The type; extremely elongate calyx, lacking the RR anal plates. 
Beech River formation; Decatur County, Tennessee. 
Thalamocrinus globosus new species 132 
Figs. 10, loa, 10b. R. post., dorsal and ventral views of the only specimen. 
Beech River formation; Decatur County, Tennessee. 
Thalamocrinus elongatus new species 132 
Fig. II. Extremely large and elongate Devonian derivitive, lacking the RR and anal plates; r. post, 
view ; differs from all the others in the wide stem, covering the entire base. 
Linden beds, Helderbergian ; near Camden, Benton County, Tennessee. 
Petalocrinus mirabalis Weller 126 
Fig. 12. A set of separate arm-fans as usually found, artificially mounted ; seen from the ventral 
side, showing 14 to 16 grooves. 
13. Similar set of arm-fans from dorsal side, showing complete fusion of arms in each radius 
into a rigid plate. 
14. A complete crown with calyx and arms in place, seen from the dorsal side, but the fused 
radii are broken away, exposing the inner floor of the ventral side, with the grooves 
indicated by ridges, in which covering plates are shown in some places. Coll. Univer- 
sity of Iowa. X 2. 
Ho'pkinton stage of Niagaran ; Jones County, Iowa. 
Petalocrinus inferior Bather 127 
Fig. 15. A nearly complete arm-fan, from ventral side, showing 28 grooves symmetrically divided 
in halves; angle of fan 70°. X 3/2. 
15a. Dorsal side of same, fused to a rigid plate. X 3/2. 
16. Another arm-fan with 30 grooves and angle of 65° ; small part missing at proximal end. 
Laurel formation ; St. Paul, Indiana. 
