642 



NORTH AMERICAN INDEX FOSSILS. 



s\ 



Black River of Canada (Encampment d'Ours, etc.). 

 122. L. mundula Ulrich. (Fig. 875, a,b.) Ordovicic. 



Differs from L. engenia in having shoulder wholly concave, 

 peripheral band high and obtuse, and umbilicus open. 



Black River of Paquette's Rapids, Canada ; Trenton of Ken- 

 tucky. 



XXXVI. Euconia Ulrich. 

 Subtrochiform shells with nearly flat base and regular conical 

 spire, the suture scarcely depressed, the 

 base umbilicated ; band on upper side of 

 peripheral edge, mouth subquadrate. Or- 

 dovicic-Siluric. 



123. E. ramsayi (Bill.). Ordovicic. 



Of medium size, regularly conic and with 

 small umbilicus. 



Beekmantown of Canada. 

 124. E. etna (Bill.). (Fig. 873.) Ordovicic. 



With wide umbilicus ; often large (2 in. in basal diameter and 

 nearly same in height). 



Beekmantown of Newfoundland. 



E. (?) pervetusta (Conrad). (Fig. 874.) Siluric. 



Fig. 873. Euconia etna- 

 A small specimen. 



125. 



(3 



Fig. 874. Euconia pervetusta. 



Small, with gently convex whorls (about four) embracing to 

 ambitus or beyond ; umbilicus large and deep, extending to apex. 

 Medina of New York. 



XXXVII. Eotomaria Ulrich and Scofield. 

 Depressed-conical pleurotomarioids, characterized by a notch 

 but not a slit, and with the band on the upper side of the periph- 

 ery ; surface with simple lines of growth. Ordovicic-Siluric. 

 126. E. dryope Bill. (Fig. 875, c-e.) Ordovicic. 



