EXPLANATION OF PLATE LXVII. 



FigS. 1-9. PSEUDOSYRINX KEOKUK n. Sp p. 408 



1-5. Posterior, anterior, lateral, pedicle and brachial views of a 

 nearly complete internal cast. Cotype. (W. M., No. 13026.) 



Residual chert. 



6-9. Posterior, anterior, pedicle and lateral views of a nearly 

 complete specimen. Cotype. (W. M., No. 13020.) 

 Keokuk limestone, Warsaw, Illinois. 



Fig. 10. PSEUDOSYRINX sp. 



View of the cardinal area of an incomplete pedicle valve. (\Y. 

 M., No. 12807.) 



Crawfordsvillc beds, Crawfordsvillc, Indiana. 



Figs. 11-13. PSEUDOSYRINX SAMPSONI Weller p. 405 



11. View of the cardinal area of an incomplete specimen appar- 

 ently belonging to this species. (W. M., No. 12816.) 



Keokuk limestone, Warsaw, Illinois. 



12-13. Posterior and anterior views of the holotype. (F. A. 

 Sampson.) 



Fern Glen formation, Fern Glen, Missouri. 



150 



