EXPLANATION OF PLATE LIV. 



Figs. 1-4. SPIRIFER ROWLEYI n. sp p. 360 



Pedicle, brachial, posterior and lateral views of the holotype. 

 (W. M., No. 13537.) 



Fern Glen formation, Fern Glcn 3 Missouri. 



Figs. 5-10. SPIRIFER CALVINI n. sp p. 368 



5. View of a pedicle valve. Cotype. (W. M., No. 13542.) 



Kindcrhook, Tauia County, Iowa. 



6-9. Pedicle, anterior, posterior and lateral views of a nearly 

 perfect specimen. 10. View of a brachial valve. Cotypes. 

 (\V. M., No. 13540.) 



Kinderhook, Lc Grand, Iowa. 



