PTEROPODA. 7 



Hyolithes herds, n. sp. 



PLATE CXIV, FIGS. '21 27. 



This species is characterized by its large size, broadly crenulated lateral mar- 

 gins, and its finely and closely striated dorsal or convex surface. 

 Lower Helderberg group. Near Clarksville, Albany county. 



STYLIOLA, Lesueuk. 1826. 



(See Vol. v. part ii. pp. 175-182.) 



Styliola spica, n. sp. 



PLATE CXIV, FIG. 28. 



This species differs from S. fissurella, Hall, of the Hamilton and Portage 

 groups, in its much greater size, more robust form, and in the absence of any 

 indications of annulations or apical node. 



Hamilton group. Hamburgh, Erie county. 



COLEOLUS, Hall. 1879. 



(See Vol. v, part ii, pp. 184-190.) 



COLEOLUS HERZERI, 11. Sp. 

 PLATE CXIV, FIG. 2!). 



The shell of this species is of unusually large size, slightly incurved toward 

 the apex, and the surface is marked by low, faint, obsolescent and somewhat 

 irregular striations. 



Waverly group. Medina county, Ohio. 



PHARETRELLA, nov. gen. 



Shell large, elongate, Hyolithes-like in outline ; apex acute, transverse section 

 probably triangular ; substance tenuous ; ornamentation consisting of trans- 

 verse, imbricating undulating striae. 



Pharetrella tenebrosa, n. sp. 



PLATE CXI V, - .FIGS.!30,'.31 . 



Genesee slate. Genesee county. 



