EXPLANATION OF PLATE XXXIV. 



Figs. 1-24. GIRTYELLA iNDiANENSis (Girty) p. 275 



1-9. Pedicle, brachial and lateral views of three nearly perfect 

 examples from the typical locality of the species. (W. M., 

 Nos. 7774 and 14237.) 



Pella Beds, Pella, Iowa. 



10-11. Pedicle and brachial views of a nearly perfect specimen. 

 (W. M., No. 14338.) 



Ste. Genevieve limestone, near Waterloo, Illinois. 

 12-17. Pedicle, brachial and lateral views of two very perfect speci- 

 mens probably belonging to this species. (D. K. G., No. 1603.) 

 Webb City, Jasper Co., Missouri. (Carterville -formation?) 

 18-20. Pedicle, brachial and lateral views of a small specimen. 

 21-24. Pedicle, brachial, lateral and anterior views of another 

 specimen. (W. M., No. 14800.) 



Lower Chester Group, Rosiclare, Illinois. 



Figs. 25-36. GIRTYELLA TURGIDA (Hall) p. 273 



25-27. Pedicle, brachial and lateral views of a large specimen. 

 28-31. Pedicle, brachial and lateral views of two smaller speci- 

 mens. (W. M., No. 14234.) 



Salem limestone, Blooinington, Indiana. 



32-C3. Brachial and lateral views of a very convex specimen. 

 34-36. Pedicle, brachial and lateral views of a small indi- 

 vidual. (W. M., No. 14771.) 



Salem limestone, Hull's Hollow, Madison Co., Illinois. 



Figs. 37-41. GIRTYELLA BREVILOBATA ( Swallow) p. 278 



37-39. Pedicle, brachial and lateral views of a very perfect speci- 

 men. (W. M., No. 7786.) 



Chester Group, Golconda, Illinois. 



40-41. Pedicle and brachial views of an internal cast. Holotype 

 of Dielasma turgida var. elongata Weller. (W. M., No. 4959.) 

 Batcsville sandstone, Batcsville, Arkansas. 



Figs. 42-47. GIRTYELLA INTERMEDIA n. sp p. 276 



42-44. Pedicle, brachial and lateral views of a very complete speci- 

 men in which the median plication in the brachial valve is 

 well developed. 45-47. Smaller views of another example 

 with the median plication of the brachial valve faintly de- 

 veloped. Cotypes. (W. M., No. 14772.) 



Paint Creek Formation, near Modoc, Randolph County, 

 Illinois. 



Figs. 48-50. GIRTYELLA CEDARENSIS n. sp p. 272 



Pedicle, brachial and lateral views of an internal cast, the holo- 

 type. The median septum is clearly shown in the brachial 

 view. (D. K. G., No. 1402.) 



Northview shale, Cedar Gap, Wright County, Missouri. 



Fig. 51. CRAN/ENA ( ?) ALLEI (Winchell) p. 252 



View of the holotype, an internal cast of the pedicle valve. (U. 

 M., No. 2004.) 



Kinderhook, Bed No. 5, Burlington, Iowa. 



79 



