PLATE XLVIl— Continued. 



Ndculites TRIQUETEK. 

 Page 3S6.. 

 See PUte 93. 

 Fig. 17. A cast of a left valve which i.s unusually acute at the t)Ost-inferior extremity. 

 Figs. 18-22. A series of specimens pi-esentiug the usiuil characters of the species. 

 Fig. 23. A caat of a lefl valve showing cituuilations on the binge-line. 



Hamilton group. Cumberland, Md. 

 Fig. 24. A gutta-percha impression from the preceding, enlarged to two diameters. 

 Kgs. 2&-'i8. A series of specimens presenting some variations from the typical forms. 



.■«i«te »mVu» aiii >|i NuCCLITES NySSA. Ma9 »rfT .1 .^ 



Page 328. 

 Vt||4l<ni'W>. Lefl and right valves. 



Hamilton gi-oup. Bighteen-mile creek, N. T. 



LeDA DIVEK8A. 

 Page 329. 

 Figs. 31-37. A series of figures showing variation in form and size, enlarged to two diameters. 



' LeDA BREVIROSTBI8. 



Page 329. 

 Figs. 38-41. A series of ligures illustrating the varieties of form, enlarged to two diameters. 



Iiiiiitaii ml' 



Leda ROSTELLATA. 

 Page 330. 

 Figs. 42-46. Present the usual varieties of form in this species. The figures are enlarged to two diameter^. 

 Fig. 47. A right valve, enlarged to three diameters. 



Hamilton group. Pratt's falls, iV. F. 



..^.,,1 i... -.„... ..,:,r,.i„„ .„iv„„;-. Leda obscura. 



Page 331. 

 Fig. 48. A right valve, enlarged to two diameters. 



Hamilton group. PiUtonham, N. Y. 



Leda PANDORIFORMIS. 

 Page 332. 

 Fig. 49. A cast of a right valve. 



Pig. 60. A gutta-percha impression from the preceding showing the characters of the hinge. 

 Waverly group. Newark, Ohio. 

 . >'.iiti -fiij ]|noi« «rua trwHini wit \o »u 



NUCULA tJMBONATA. 



Page 321. iftollUn /a 



Figs. 51, 52. Left and caHinal views of a ca.st. niiiian 



Chemung gi-oup. Maiixfield, Pa. 



SoLEMYA (JaNEIA) VETU8TA. 

 Page 463. 

 See Plate 94. 

 Figs. 63-£5. Right, left and cardinal views of a characteristic specimen. 

 Hamilton group. Near LouisviUe, Ky. 



