EXPLANATION OF PLATE VIII. 



Figs. 1-7. CHONETES SHUMARDANUS DeKoninck p. 89 



1. Pedicle valve of a large individual. 2-3. Pedicle and brachial 

 views of a specimen preserving both valves. 4-5. Pedicle and 

 brachial views of another specimen preserving both valves. 

 6-7. Exterior and interior views of a pedicle valve. (W. M., 

 No. 13940.) 



New Providence shale, Button Mould Knob, Kentucky. 



Figs. 8-16. CHONETES MULTICOSTA Winchell p. 79 



8-9. Pedicle and brachial views of a large example preserving 

 both valves. (W. M., No. 4700.) 



Fern Glen formation, Fern Glen, Missouri. 



10-11. Views of two large pedicle valves. (W. M., No. 352.) 

 Burlington limestone, near Springfield, Missouri. 



12. View of a pedicle valve, the principal one of Winchell's types. 

 (U. M., No. 1343.) 



Lo-ii'er Burlington limestone (?), Burlington, Iowa. 



13. View of a brachial valve, one of Winchell's types. (U. M., 

 No. 1343.) 



White chert, probably from the Lozver Burlington limestone, 

 Burlington, lozva. 



14-15. External impressions of two brachial valves. 16. An 

 internal cast of a pedicle valve. (U. M., No. 1343.) 

 Kinderhook, bed No. 7, Burlington, Iowa. 



Fig. 17. CHONETES sp. 



The internal cast of a pedicle valve included among the types of 

 C. multicosta Winchell. (U. M., No. 1343.) 

 Chonopcctits sandstone, Burlington, Iowa. 



Figs. 18-19. CHONETES BURLINGTONENSIS Weller p. 93 



18. View of a pedicle valve, the holotype. (W. M., No. 6669.) 



19. View of a brachial valve. (W. M., No. 13943.) 



Kinderhook oolite, bed A r o. 6, Burlington, Iowa. 



Fig. 20. CHONETES MISSOURIENSIS n. sp p. 82 



View of a large pedicle valve, the holotype. (W. M., No. 8560.) 

 Pierson limestone, near Springfield, Missouri. 



Figs. 21-29. CHONETES ORNATUS Shumard p. 86 



21-24. Pedicle views of four nearly perfect individuals. 

 25-28. Brachial views of the same four individuals. 

 29. View of the interior of a brachial valve. (W. M., 

 No. 6726.) 



Louisiana limestone, Louisiana, Missouri. 



Fig. 30. CHONETES GLENPARKENSIS Weller p. 87 



View of a pedicle valve, the holotype. (W. M., No. 11355.) 

 Glen Park limestone, Glen Park, Missouri. 



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