128 Cincinnati Society of Natural History. 
2.2 mm.; greatest height, 1.1 mm.; length of body of valve, 1.5 
mm.; height of same, 0.8 mm.; convexity of same, 0.25 mm.; 
width of marginal area at anterior extremity, o.4 mm.; width of 
same at ventral and postero-ventral margins, 0.3 mm. 
This species is more elongate than any of the others. The ogee 
molding of the marginal area also serves to distinguish it. 
Position and locality: Birdseye limestone, at High Bridge, Ky.; 
and ‘‘ Glade limestone,’’ of Central Tennessee. 
EURYCHILINA GRANOSA, N. Sp. 
Flate 1X, Figs. 9, 10, 11 ana 12 
Valves elongate-subelliptical ; about 1.7 mm. long by 1.15 mm. 
high. Dorsal margin straight, often appearing a little convex, 
forming nearly a right angle with the anterior margin. This 
curves neatly into the convex ventral edge, and from there up 
again into the more rounded posterior end; scarcely forming an 
angle where the latter joins the dorsal margin. Body of valve 
strongly convex, with a rather narrow and deeply impressed mesial 
sulcus, and just behind it a prominent round tubercle. Central 
portion of surface with small yet quite distinct granules. Marginal 
area separated from body of valve by a sharply impressed line, 
convex, strongly bent in, typically smooth, and terminated by a 
narrow flange which in young examples is represented by a closely 
arranged row of small spines. Width of area greatest along the 
ventral border, where it is about 0.3 mm., becoming gradually 
narrower toward the dorsal angles, where it is less than half that 
width. 
A variety, represented by figure 11, differs in having a more 
elongate form, stronger tubercle, and the marginal area covered 
with fine, interrupted concentric strie. The marginal flange is 
also absent. It is associated with the more typical examples. 
The tubercle, granulose surface, and narrower marginal area 
distinguish this species from 4. @gualis. It is shorter, the tuber- 
cle stronger, and the marginal area differently curved than in Z. 
longula. 
Position and locality: Chazy limestone, bottom of gorge of 
Kentucky River, at High Bridge, Ky. 
