235 



GRAMMATODON INORNATTJS, Meek and Hayden. 

 Plate 31, figs. 8, 8a, and 86. 



Area (Cucull&a) inornata, Meek and Hayden. 1858. Proceedings of the Aca- 



demy of Natural Sciences of 

 Philadelphia, p. 51. 

 Orammatodon inornatus, Meek and Hayden. 1862. Idem, p. 419. 



". " " " 1864. Palaeontology of the Up- 



per Missouri, p. 90, pi. 3, figs. 

 9, 9a and 96. 



" " Whitfield. 1880. Geology of the Black 



Hills of Dakota, p. 359, pi. 5, 

 figs. 16-18. 



North shore of Cumshewa Inlet, one nearly perfect specimen with 

 the valves widely open and partly clasping a valve of Irwceramus con- 

 centricus. 



Skidegate Inlet, south side of Alliford Bay, four specimens : and Bay 

 east of Alliford Bay, one imperfect example. 



CUCULL^A (IDONEARCA). Species undeterminable. 

 Outullcea (?). Sp. Undt. This volume, page 73. 



East end of Maud Island : a crushed and imperfect specimen which, 

 however, has the sculpture well preserved on both valves. 



The surface markings consist of very numerous and densely crowded 

 concentric raised lines, which are crossed by radiating stria?. On the 

 posterior and central portions of the sides of the valves the radiating 

 striae are close together and not much elevated, but near the anterior 

 margin they are distant, prominent and very acute. 



TRIGONOARCA TUMIDA. (N. Sp.) 

 Plate 31, fig. 6. 



Shell inflated, tumid, the thickness through the closed valves being 

 apparently a little greater than their maximum height : valves trans- 

 versely elongated and very inequilateral : anterior end short, rounding 

 up broadly and obliquely from below and forming a sharply angular 

 junction with the superior border above. Superior border nearly 

 straight both in front and behind, but sloping very gently downwards 



