322 



Mesotrypa dubia n. sp. 



1. Tangeutial section x 20. 



2. Longitudinal section x 20. 



Pierce limestone. Murfreesboro, Toun. 



Dekayella ridleyana n. sp . 



3. Longitudinal section x IS. 



4. Tangential section x IS. 

 Kidley limestone. Salem, Tonn. 



Heterotrypa patera n. sp . 



5. Longitudinal section x 18. 



6. Tangential section x 18. 



Pierce limestone. Stokes fiannon Ford. 2 miles northwest of Mur- 

 freesboro, Tenn. 



