EXPLANATION OF PLATE L. 



Figs. 1-5. SPIRIFER LITTONI Swallow p. 348 



Pedicle, brachial, lateral, posterior and anterior views of a very 

 perfect specimen. (W. M., No. 14775.) 

 St. Louis limestone, Alton, Illinois. 



Figs. 6-12. SPIRIFER INDIANENS'IS n. sp p. 352 



6-10. Pedicle, brachial, lateral, posterior and anterior views of a 

 partially restored specimen. 11-12. Views of two pedicle valves. 

 Cotypes. (W. M., No. 7493.) 



Harrodsburg limestone, Spergen Hill, Indiana. 



Figs. 13-14. SPIRIFER MARSHALLENSIS n. sp p. 349 



Views of two brachial valves. Cotypes. (W. M., No. 13541.) 

 Kinderhook, LeGrand, Iowa. 



Figs. 15-22. SPIRIFER SUBROTUNDUS n. nom p. 356 



15-18. Pedicle, brachial, lateral and anterior views of a nearly com- 

 plete specimen. (W. M., No. 8618.) 19-22. Pedicle, brachial, 

 lateral and anterior views of another specimen. (W. M., 

 No. 5932.) 



Chonopectus sandstone. Burlington. loi^a. 



116 



