302 S. WELLER FAUNA OF THE FERN GLEN FORMATION 



CAMAROTCECHIA PERSINUATA (Winchell) 

 Plate 12, figures 24-25 



1865. Rhynchonella persinuata Winchell, Proceedings of the Academy of Nat- 

 ural Science of Philadelphia, page 121. 



1901. Camarotcechia persinuata Weller, Transactions of the Academy of Sci- 

 ences of Saint Louis, volume 11, page 197, plate 19, figure 5. 



Description. — Shell of medium size, broadly subovate in outline, 

 broader than long, the greatest width at or in front of the middle. Ped- 

 icle valve depressed convex in the umbonal region, the surface rounding 

 rather abruptly to the postero-lateral margins, the median portion de- 

 pressed abruptly anteriorly in a broad, nearly flat mesial sinus which is 

 produced into a broad lingual extension in front at nearly a right angle 

 to the plane of the valve. Brachial valve subpyramidal in form, most 

 prominent near the anterior margin, the surface rounding more abruptly 

 to the antero-lateral margins. Surface of each valve marked by simple, 

 angular or subangular plications, of which usually seven occupy the 

 mesial sinus and eight the fold and about eight or nine each lateral slope 

 of each valve; around the anterior and lateral margins the grooves be- 

 tween the plications are produced into extended, acutely angular ser- 

 rations which fit into corresponding angular notches in the ribs of the 

 opposite valve. 



The dimensions of a crushed example of this species are: Length, 16 

 millimeters; width, 17.5 millimeters. 



Remarks. — This species is represented in the Fern Glen collections, 

 which have been available for study, only by much crushed individuals. 

 These specimens, however, are clearly identical with this species, which 

 was described by Winchell from the highest Kinderhook bed at Burling- 

 ton, Iowa, and a part of the characters mentioned in the above description 

 have been taken from an excellent example from Burlington. 



The shell from Lake valley, New Mexico, which has been described by 

 Miller as Camarophoria occidentalis, is similar to the present species and 

 is, perhaps, identical with it. In neither the description nor the illus- 

 trations of the New Mexican shell are the essential features of the genus 

 Camarophoria indicated, and there need be no hesitation in considering 

 it as congeneric with this Fern Glen shell, even if it is not the same 

 species. 



SPIRIFER VERN0NEN8I8 Stvallow 



Plate 13, figures 3-8 



1860. Spirifer vernonensis Swallow, Transactions of the Academy of Science 

 of Saint Louis, volume 1, page 644. 



