EXPLANATION OF PLATE XXV. 



Figs. 1-6. ALLORHYNCHUS MACRA (Hall) p. 199 



1-2, 3-4. Pedicle and brachial views of two examples of about maxi- 

 mum size. (W. M., No. 13936.) 



Salem limestone, Hull's Hollow, above Alton, Illinois. 

 5-6. Pedicle and brachial views (x4) of a small example having 

 the characteristics of Rhynchonella ricinula Hall. (W. M., 

 No. 2992.) 



Salem limestone, Stinesville, Indiana. 



Figs. 7-17. PUGNOIDES OTTUMWA (White) p. 193 



7-9. Pedicle, brachial and posterior views of a large and broad 

 specimen. 10-11, 12-13. Pedicle and brachial views of two very 

 perfect examples. 14-17. Pedicle, brachial, anterior and poste- 

 rior views of a nearly perfect specimen. (W. M., No. 13930.) 

 Ste. Genevieve limestone, Fountain Creek, near Waterloo, 

 Illinois. 



Figs. 18-21. RHYNCHOPORA (?) PERRYENSIS n. sp p. 239 



Pedicle, brachial, anterior and lateral views of a very perfect speci- 

 men. (D. K. G., No. 2304.) 



Landing 76, Perry County, Missouri. 



Figs. 22-26. PUGNOIDES BOONENSIS (Shumard) p. 195 



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

 perfect specimen. (D. K. G., No. 2201.) 



Burlington limestone, Louisiana, Missouri. 



Figs. 27-33. LIORHYNCHUS GREENIANUM (Ulrich) p. 185 



27-30. Pedicle, brachial, anterior and lateral views of a very perfect 

 internal cast. 31-33. Brachial, lateral and anterior views of 

 another specimen. (W. M., No. 13645.) 



Knobstone shale, New Albany, Indiana. 



Figs. 34-36. PUGNAX QUADRIROSTRIS Beede p. 204 



Pedicle, brachial and lateral views of a very perfect individual (x4). 

 (W. M., No. 2996.) 



Salem limestone, Bloomington, Indiana. 



Figs. 37-42. PUGNAX WORTHENI (Hall) p. 203 



37-39. Pedicle, brachial and anterior views of a large and nearly 

 perfect specimen. (W. M., No. 13928.) 



Salem limestone, Hull's Hollow, above Alton, Illinois. 

 40-42. Similar views of the holotype. (A. M. N. H., No. 5064.) 

 Salem limestone, near Alton, Illinois. 



Figs. 43-52. SHUMARDELLA MISSOURIENSIS (Shumard) p. 222 



43-47. Pedicle, brachial, anterior, posterior and lateral views of a 

 nearly perfect specimen. 48-52. Similar views of another 

 specimen. (W. M., No. 9667.) 



Chouteau limestone, Chouteau Springs, Missouri. 



58 



