PLATE IV 
Fig. 1. Agelacrinus holbrooki, James. Showing the interambulacral plates 
between rays Nos. 1 and 2. Specimen No. 1004, in the James Collection at Chicago 
University Labelled as coming from near Lebanon, Ohio, and cited by John M. 
Nickles from the Corryville member of the Alaysville formation. 
Fig. 2. Streptaster septembrachiatus, Aliller and Dyer. Under surface of up- 
])er or oral side of theca, showing the substomial chamber with the deep cavity or 
aperture at its posterior margin, and the inclined surface at the left of this margin. 
The floor plates are shown along the narrow bases of all the rays, and very much 
fore-shortened covering plates are seen along the side of the rays. Along the right 
margin of the figure some of the plates belonging to the inner band of the 
peripheral ring are nearly horizontal. From the Elkhorn member of the Rich- 
mond, six and a half miles west of the courthouse at Dayton, a sixth of a mile north 
of the Eaton pike, and about the sam.e distance west of the Union road which 
leads northward to Trotwood, Ohio. 
Fig. 3. Streptaster reversata, sp. nov. Fragment showing posterior half of 
theca, including nearly all of rays 1 and 5, with the intermediate posterior or anal 
interambulacral area; the latter shows the mosaic of small polygonal interambu- 
lacral plates; and the anal pyramid. Small interambulacral plates are shown also 
between ray No. 1 and the distal half of ray No. 2; also on the left of ray No. 2, as 
far up as the tip of ray No. 3. The upper edges of the large plates forming the 
inner band of the peripheral ring are well exposed, but only a part of the marginal 
])lates of this ring are seen at several points. West of tressel51, about two miles 
west of Million, in Aladison County, Kentucky, west of Richmond. Horizon 
not definitely known but regarded as middle Eden Magnified 4.4 diameters. 
Fig. 4. Vallatotheca manitoulini, Gen. et sp. nov. A, Lateral view; B, viewed 
from above. Genotype, differing from the congeneric Stenotheca unguiformis, 
Ldrich, in its much larger size and the greater curvature of the beak. The con- 
centric markings are not due to transvei'se folds, but are successive lamellose out- 
growths of the shell, striated only on their api al sides. From the Cape Smyth or 
Waynesville member of the Richmond, at the Clay Cliffs, on the eastern side of 
Cape Smyth, three miles north of Wekwemikongsing, on the eastern shore of Mani- 
toulin Island. Specimen No. 8448, in the collections of the Geological Survey of 
Canada, in Victoria Memorial Museum, at Ottawa, Canada. 
Fig. 5. Rhytimya kagawongensis, sp. nov. Mesial sulcus faint o ’ obsolete. 
Concentric lines not more prominent anteriorly. Radiate lines, 7 to 10 in a 
width of 3 mm. on the postenor parts of the shell, increasing to 12 and more 
in same width anteriorly; consisting of discrete granules, enlarging in size pos- 
teriorly, where 6 may occur in a length of 1 mm. Characterized by its even and 
comparatively strong convexity, the umbonal ridge being only slightly defined at 
the beak, merging into the general convexity of the shell. Along the road from 
Kagawong to Gore Bay, several hundred yards before leaching the margin of the 
outcrop of the Cataract limestone, about two miles southwest of Kagawong, on 
Manitoulin Island. Specimen No. 8449, in the collections of the Geological 
Survey of Canada, in the Victoria Memorial Museum, at Ottawa, Canada. 
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