Figs. 41-48. SPIRIFERINA NORWOODANA (Hall) p. 295 



41-44. Posterior, lateral, brachial and pedicle views of a nearly 

 perfect specimen (x 4). 45-48. Pedicle, brachial, lateral and 

 anterior views of a nearly perfect specimen. (x 4.) (W. 

 M., No. 5636.) 



Salem limestone, Blooiiiington, Indiana. 



Figs. 49-53. DELTHYRIS SIMILIS n. sp p. 305 



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

 perfect internal cast, the holotype. ( D. K. G., No. 2903.) 

 Residual chert, South Branch, Callaway Co., Missouri. 



Figs. 54-57. SPIRIFERINA SUBELLIPTICA (McChesney) p. 294 



54-55. Pedicle and brachial views of a sulphur cast of the holo- 

 type. (W. M., No. 13239.) 



Button Mould Knob, Kentucky. 



56. View of a pedicle valve. 57. View of the interior of a ped- 

 icle valve showing the median septum. (W. M., No. 13427.) 

 Lebanon, Kentucky. 



