54 



Aucr. F. Focrste 



pears anteriorly. The radiating striae are of medinm coarseness, 

 compared with those selected as types of HehertcUa sinuata and 

 HcbcrtcUa subjugata. Specimens of this type are fairly common 

 in the Richmond, ranging from the Arnheim to the Elkhorn. Ixit 

 they are especially common in the Liberty bed and in the upper 

 part of the Waynesville. Forms apparently identical in character 

 appear as low as the Corryville and upper 'Fairmoiint. It is not 

 known from what horizon the types were obtained. They are 

 labelled as coming from Cincinnati, Ohio, but this labelling fre- 

 quently was used for specimens obtained from Richmond strata by 

 the Cincinnati collectors. 



In the original description, HcbcrtcUa 'occidcntalis is cited from 

 Maysville, Kentucky. Cincinnati and Oxford, Ohio, and Madison, 

 Indiana. The Maysville and Cincinnati exposures probably were 

 both in the Maysville formation. The Oxford and Madison speci- 

 mens probably came from Richmond strata. This favors the source 

 of the type specimens from the Maysville formation. 



The specimen represented by figs. 2a, g, i, on plate 32 A, of 

 the New York Paleontology, vol. i, is too small to show the 

 characteristic features of the species, as described, very well, and 

 the originals of figs. 2b and d can not be identified. Therefore the 

 specimen illustrated by figs. 2 c, k, and the one illustrated by figure 

 o, on the same plate have been selected for illustration in the 

 present paper. 



Hebertella subjugata, Hall. 



(Plate II, fig. 8.) 



HcbcrtcUa subjugata differs from HcbcrtcUa occidcntalis and 

 HebcrtcUa sinuata chiefly in the finer plications. There is no 

 median depression near the beak of the brachial valve. 



Specimens of this type are common in the lower and middle 

 Eden, as exposed between Sadieville and Rogers Gap, and both 

 east and w-est of Million, in Kentucky. At Cincinnati, similar 

 specimens range from the Mount Hope bed upward through the 

 Maysville, being more common in the lower beds. It occurs also 

 in the Waynesville bed, and probably higher in the Richmond. 



In the original description of this species, Cincinnati and 

 Oxford. Ohio. Maysville. Kentucky, and Madison. Indiana, are 

 mentioned, ddiis favors the Mavsville formation as the source of 



