PLATE LXXVIII—Continued. 
Pholadella Newberryi. 
Page 471. 
Fig-. 25. A left valve showing- the form and surface marking's. The posterior extremity is restored in the 
tig-ure. Waverly group. Licking Co., Ohio. 
Grammysta constricta. 
Pag-e 377. 
See Plate 59. 
Figs. 26, 27. Two light valves enlarged to two diameters showing the form and surface characters. 
Fig-. 26, Hamilton group. Otsego Co., N. Y. 
Promacrus cuneatus. 
Page 510. 
Fig. 28. The anterior portion of an imperfect right valve. 
Burling-ton sandstone. Burlington, Iowa. 
ORTHONOTA ? PARVULA. 
Page 482. 
See Plate 65. 
Figs. 29-32. Four specimens retaining both valves in conjunction, showing some variation in size and pro¬ 
portion. Figs. 29, 30 and 31, enlarged to two diameters. 
Hamilton group. IF. Y. 
SOLEN (PaLIEOSOLEN) SIL1QUOIDEA. 
Page 483. 
Fig. 33. The right valve described. 
Hamilton group. Schoharie Co., IF. Y. 
Orthonota oarinata. 
Page 479. 
Fig. 34. A specimen retaining both valves conjoined along the hinge, enlarged to two diameters. 
Hamilton group. Shore of Cayuga lake, IF. Y. 
Fig. 35. A right valve, natural size. The posterior extremity is incorrectly restored in outline. 
Orthonota ENSIFORMIS. 
Page 480. 
Fig. 36. A view of the right valve described as obtained from a gutta-percha impression of the natural 
mould. Hamilton group, Schoharie Co., IF. Y. 
Orthonota unhulata. 
Page 478. 
Fig. 37. A young individual retaining both valves. 
Hamilton group. Bear's gulf , Schoharie Co., IF. Y. 
Fig. 38. A specimen of medium size preserving both valves, conjoined at the hinge-line. 
Hamilton group. Bear's gulf, Schoharie Co., N. Y. 
Figs. 39, 40. Left and right valves showing the form and surface characters. 
Hamilton group; Schoharie Co., IF. Y. 
Fig. 41. The rig-ht side of a large specimen. 
Hamilton group. Bear's gulf, Schoharie Co., N. Y. 
Fig. 42. The right side of a somewhat smaller individual. 
Hamilton group. Fultonham, Schoharie Co., IF. Y. 
