(PLATE CXIV— Continued. 



TeNTACULITES DEXITHEA, 11. S[). 

 l'age 6. 

 Fie. I s - Three individuals of the species upon a block of sandstone. 



Fig-. 19. The si imen on the right of the block in the, preceding figure, enlarged to two diameters. The 



upper portion of the | n is preserved as a cast of the interior, the lower portion retaining 



tin- crust. Tli'- species differs from T. scalarifoi mis in its much more elongate and slender form 

 anil its more sloping annuli. 



Upper Helderberg group. From the sandstones at. the base of tin ('< rnift runs Hun stone 

 at Pendleton, Indiana. 



Tentaculites scalariformis. Hull. 



Page 6. 



Fig. 20, A block of limestone bearing numerous individuals of this S] tes* all of which are flattened and 



consequently made to appeal' relatively too broad. 



Comiferpus limestone. Delaware, Delawap counpy, <>hio. 



Hyolithes centennialis. Barrett. 



Page 6. 

 Fig. 21. A fragment of a small specimen of this species which was intended to represent the ventral side 

 of the shell, but the left edge of the drawing isthe axial line of the convex or dorsal surface, and 

 the surface represented is the right dorsal slope. The specimen shows the faint longitudinal 

 stria' near the lateral margin. 



Lower Helderberg group. Port Jerris, Orange county. 

 Fig. 22. Dorsal view of a large individual, showing the character .of the ornamentation, which consists of 



elevated, transverse, sinuous lines. 1 ing obsolete near margins. The edges of these striae 



are sometimes faintly crenulate. 

 Fig. 23. A portion of the surface of another specimen enlarged to two diameters, showing the crenulation 

 of the' transverse striae. 



Lower Helderberg group. Port Juris, Orange county. 



Hyolithes iieros, n. sp: 



Page 7. 



Fig. 24. The ventral surface of a specimen from which the apical portion has been lost, showing the faint 

 tranverse lines and two longitudinal furrows which extend nearly two-thirds the entire length 

 of the shell. 



Fig. 2f>. The dorsal surface of the same specimen, showing the fine longitudinal striae and the broad mar- 

 ginal undulations. 



Fig. 26. A portion of the dorsal surface, enlarged to two diameters, showing the character of the orna- 

 mentation. 



Fig. 27. Transverse section of the same specimen, showing the degree of convexity of the dorsal and ventral 

 surfaces. 



Lower Helderberg group. Near Clarksville., Albany county, 



Styliola spica, n. sp. 



Page 7. 

 Fig. 28. An individual enlarged to two diameters, showing the symmetrical uncompressed form and smooth 



surface. This s] ies differs from (ityliulit Jissurilia in its comparatively great size, and the 



entire absence of indications of transverse annuli. 

 Hamilton group. Hamburgh, Erie county. 



COLEOLUS IlERZERI, 11. Sp. 

 Page 7. 

 Fig. 29. A nearly entire individual showing the gently incurved form and the faint obliquely transverse 

 striae. Waverlj group. Medina, Ohio. 



1'llARETRELLA TEXEHROSA, II. Sp. 



Page 7. 



Fig. 30. An individual of tins species', showing the Hyolithes-like form and the tine, sinuous, transverse 



striae, 'lie- substance of the shell is extremely thin and delicate and the stria? are slightly 



imbricating. 



Fig. 31. A portion el the surface of the same specimen enlarged to two diameters, showing the character 



of tl rnamentation. 



Hamilton group (Genesee shales). Genesee county. 



