Raymond: Fauna ok iiih .\i,i.K(;henv Skriks. 151 



in the section in Kansas than is yet known for them in Pennsylvania, 

 where they are restricted to certain horizons in the Coneniau^h. On the 

 basis of sucli meager exidence it is very iinsife to venture any (h'finite 

 correlations, but it seems possible that the horizons of the Vanport and 

 Parsons limestones may approximately correspond, and that the lime- 

 stones of the Conemaui^ii were deposited at about the same time as the 

 Lecompton and some of the limestones above it. The limestones be- 

 tween the Parsons and the Lecompton would then represent marine 

 deposits in Kansas at a time when western Pennsylvania was above tide- 

 level, and would account for the abrupt break in the sequence in faunas 

 in this State and the greater range of the species in Kansas. 



It is to be regretted that there are not more faunal lists with which to 

 compare those here presented. Lists showing the range of the species in 

 Ohio, Kentucky, Indiana, and Illinois might throw a great deal of light 

 on the correlation of the coal-measures of those States. 



Descriptions of New Species. 

 Class Brachiopoda. 

 Family DISCI NID^ Gray. 

 Genus Orbiculoidea d'Orbigny. 

 Orbiculoidea planodisca sp. nov. 

 Plate XXVIII, figures 12, 13. 

 Shell elliptical in outline, three-fourths as wide as long. The brachial 

 valve is depressed convex, with the apex close to the posterior margin. 

 The outline of the pedicle valve is not regularly elliptical, but the sides 

 are somwhat pinched together and straightened back of the apex. On 

 this, valve the apex is low, nearly central, and the pedicle furrow extends 

 behind it almost to the margin. The surface of both valves is marked 

 by concentric growth lines, and the interior of the brachial valve is marked 

 by a number of fine lines radiating from the beak. 



One of the best preserved brachial valves is 24 millimeters long and 1 8 

 mm. wide. 



One other Orbiculoidea with a submarginal beak is known from the 

 Pennsyhanian. This is 0. miitida (Miller and Gurley) from Kansas City, 

 Missouri. The brachial valve of that shell is much more convex than 

 that of the species here described, and the sides are more nearly straight. 

 The pedicle \alve of 0. munda is not known. 



Locality. — The specimens here described were found in the upper part 



