PLATK LI— Continued. 



PaLvKONEILO CONSTKICTA. 

 r««e333. l>] 

 Sec Plate 48. 

 Vig. 17. A left valve, enUrg«d. ttz/H vriuio 



Portanfe group. Near Portland Harbor, N. T. 



NUCULA LAMELLATA. 

 l"agc 3i0. 

 See PlatcR 45, 93. 



V\g. 18. A right valve, enlarged. 



Hamilton group. iSkore of Cayriya lake, N. Y. 

 Fig. 19. A specimen retaining the two valves in conjunction, enlarged. 



Hamilton gi-oup. Shore of Cayuga lake, N. T. 

 Fig. 20. A left valve, enlarged. 

 Fig. 21. A right valve, enlarged. 



Hamilton group. Sliore of Cuytiga lake, iV. Y. 



Ptvchodesma Knappianum. 



Page ■i.'ii. 

 Kga. 22, 23. Cardinal views of two specimens. 



Figs. 24-2(i. Left and two right valves showing some variation in form. 

 Fig. 27. An enlargement of one side of the ligainental area. 



Hamilton group. Near Lmiiisville, Ky., and Clarke County, Indiana. 



Dystaotella telliniformis. 



Page 51ij. 

 Figs. 28, 29. Lateral and cardinal views of a .small specimen. 



Coniifei-ous limestone. Canada West. 

 Fig. 80. A cast of the interior preserving the remains of some concentric undulations. The specimen is 

 imperfect, and is completed in the figure by comparison with other individuals. 

 Coniifei-ous limestone. Canada West- 

 Fig. 31. A cast of the interior of a specimen. 



CoiTiiferous limestone. Western New York. 



DySTACTELLA SUBNA8UTA. 

 Page 51:i. 

 See Plate 95. 

 Fig. 32. The left side of a specimen showing mu.scular scar and pallial line. 

 Fig. 33. The right side of a specimen preserving the concentric strise. 

 Comiferous limestone. Near Louisville, Ky. 



