The !N'ew Species of Beachiopoda. 387 



surface of the valves smooth or covered with concentric sub- 

 lamellose growth-lines. Length of an upper valve, 11 mm.; width, 

 12 mm. ; diameter of a lower valve, 16 mm. 

 Trenton shale. Minneapolis^ Minnesota. 



Pholidops calceola. 



Plates, fig. 20. 



Pholidop* calceola, Hall. Palaeontology of N. Y., vol. VIII, pt. 1, p. 182, 

 pi. ivi, fig. 30. 1892. 



Shell small. Outline subelliptical, the posterior margin being 

 narrowed by the extension of the beak, which is long and acute, 

 slightly elevated above the plane of the margin. External surface 

 marked by concentric lamellose growth-lines, which extend about 

 the posterior side of the beak. Muscular area central ; posterior 

 margin divided into a broad central and two lateral arches, from 

 the latter the outline extending in a regular curve to the anterior 

 margin. Adductor scars sharply defined. The dorsal (?) valve 

 only is known. Length of the original specimen, 3.5 mm. 



Corniferous limestone. Falls of the Ohio. 



Pholidops patina. 



Plates, figs 17-19. 



Pholidops patina, Hall. Palaeontology of N. Y., vol. VIII, pt. 1, p. 182, pi. 

 ivi, figs. 27-29. 1892. 



Shell comparatively large ; outline elongate-ovate or elliptical. 

 Length to width as 3 to 4. Apex posterior. Surface covered 

 with lamellose concentric growth-lines, which are crossed by 

 fine, interrupted radiating strise. The interior of the ventral (?) 

 valve has the anterior and posterior adductors well defined, the 

 latter being lobate. The median scars are well developed and 

 the parietal impression acutely angled at the center. In the 

 opposite valve the anterior edges of the muscular area are 

 sharply elevated, both pairs of adductor scars prominent, and the 

 parietal scar extended posteriorly. 



Corniferous limestone ; from boulders of decomposed chert. 

 DeCenwille^ Ontario. 



43 



