NO. 2297. BRACUlOrOD GENUS PLATYSTROPHIA—McEWAN. 44;^ 



Plate 45. 



All figures on this plate are natural size. 

 Figs. 1-4. Plati/strophia dnrksvillensis Foerste, p. 422. 



1. Cardinal view shoMnng the extended hinge line. 



2. Pedicle valve. The specimen shows the subequal plications in the gimi.-'. 



3. Anterior view. The prominent sinus is characteristic. 

 Richmond groui> (Wayne.^ville formation), Wayneaville, Ohio. 



4. Brachial valve. 



Richmond group (Waynesville formation), Oregonia, Ohio. 

 Figs. 5-8. Plati/sfropJtia waUoiraijl Foerste, p. 438. 



5. Anterior view showing the great depth of the sinus. 

 Richmond group (Arnheim), Soiitheastern Indiana. 



6. Lateral view. The robust form is characteristic. 



7. Brachial valve. The figure shows the tj^^ical strong varices. 



8. Pedicle valve of a mutation ^vith four plications in the sinus. 



Richmond group (Arnheim). Long Run, three-fourths mile above I'.OHum. 

 Jefferson County, Kentucky. 

 Figs. 9-13. Platystrophia cuminffsi, new species, p. 422. 



9. Pedicle valve. The figure represents an average specimen. 

 Richmond group (Waynesville formation), Oxford, Butler County, Ohio. 



10. Cardinal view. The ventricose form is characteristic. 

 Richmond group (Waynesville formation), Oregonia, Ohio. 



11. Brachial valve showing the strong plications on the slopes of the fold. 



12. Anterior view of a mutation which has four plications in the sinus. 

 Richmond group (Waynesville formation), WaynesA'ille, Ohio. 



13. Brachial valve. The right side has been crushed. 

 Richmond group (Fernvale limestone), Wilmington, Illinois. 



Figs. 14-16. Platt/strophia cf. cumingsl, new species, p. 422. 



14. Anterior view showing shallow sinus, low fold and thin valves. 



15. Pedicle valve. The extended cardinal extremes is characteristic. 



16. Brachial valve. 



Richmond group, near Waynesville, Ohio. 

 Figs. 17-19. Plati/strophia sublaticosta, new species, p. 419. 



17. Anterior view. The shallow sinus and low fold are t\q:)ical. 



18. Brachial valve showing the strong plications on the slopes of the fold. 



19. Pedicle valve. (Same specimen as fig. 17.) 

 Maysville group (Upper Fairmount), Cincinnati, (Jhio. 



Figs. 20-21. Platt/strophia acutilirata (Conrad), p. 424. 



20. Interior of pedicle valve. 



21. Brachial valve. The low broad fold is typical. 

 Richmond group (Whitewater), Richmond, Indiana. 



Fig. 22. Platyslrophia acutilirata prolongata Foerste, p. 425. 



22. Pedicle valve showing the extended cardinal extremities. 

 Richmond group (Whitewater formation), Richmond, Indiana. 



Fig. 23. Platyslrophia acutilirata senex Cumings, p. 426. 



23. Brachial valve. The narrow form is characteristic. 



Richmond group (Upper Whitewater formation), Richmond, Indiana. 



Plate 46. 



Al! the figures on this plate are natural size. 

 Figs. 1-4. Platystrophia attenuata, new species, p. 421. 



1. Pedicle valve. The figure illustrates the broad shallow sinus. 



2. Anterior A-iew showing the characteristic thin form. 



