PLATE IX. 
Crenipecten Wtnchelli. 
Page 89. 
Figs. 1, 2, 4. Small right valves showing the form of this valve and the obsolescent surface markings. 
Figs. 25, 26, 27, Three left valves. Fig. 25 incorrectly represents the specimen as having the form of a 
right valve. The beak should- turn slightly toward the left and the posterior margin 
should be more extended. 
Fig. 28. The upper portion of a left valve, enlarged , to two diameters, showing the form and surface 
characters of the ears, and the transverse lig-amental grooves or cartilage pits. 
Fig. 29. An enlargement of the surface as obtained from an impression taken in the natural mould of the 
exterior. 
Fig. 30. An enlargement as Shown in an impression of the exterior left in the matrix. 
Waverly sandstone. Newark, Ohio. 
Fig. 
Aviculopecten (Crenipecten ?) incultus. 
Page 30. 
An impression of the interior of a right valve. 
Chemung group. Olean, N. Y. 
Aviculopecten Caroli. 
Fig. 
A partially exfoliated left valve. 
. Waverly sandstone. 
Page 29. 
'Newark, Ohio. 
Crenipecten crenulaTus. 
Page 82. 
Figs. 6-8. Three left valves varying somewhat in form and obliquity. 1 
Chemung group. Rockville, Alleghany Oo., N. Y. 
Fig. 15. A right valve showing the form of this valve and the row of minute cartilage-pits along the hinge. 
The posterior ear is not sufficiently extended in the figure. 
Chemung group. Philipsburg, Alleghany Co., N. Y. 
Fig. 16. A right valve. The posterior ear in the specimen is somewhat larger than represented. 
Fig. 17. An enlargement, to two diameters, showing the row of-cartilage-pits along the hinge. 
Chemung group. Rockville, N. Y. 
