208 Cincinnati Society of Natural Fitstory. 
central one of the three eminences that have suggested the specific 
name. 
Position and locality: Shaly limestones of the Chester group, 
near Grayson Springs and Leitchfield, Ky. 
KIRKBYA VENOSA, Nl. Sp. 
Plate XVIII, Figs. 3 a, b. 
Size: Length, 0.75 mm.; height, 0.48 mm.; thickness of one 
valve, 0.15 mm. 
Valves subelliptical, symmetrical, with the back straight, ventral 
edge nearly so, ends semicircular, equal; cardinal angles obtuse. 
A depressed and slightly concave marginal space, wide at the ends, 
narrow at the center of the ventral edge, encloses the elevated 
main body of the valve. This is traversed by flexuous, narrow, 
vein-like, longitudinal ridges. Spaces between ridges minutely 
reticulate. Umbilical pit round, situated above the center in a 
hollow between two of the ridges. 
This species is near XK. flicata, Jones and Kirkby, but in that 
species there is no depressed marginal area, and the longitudinal 
ridges or plications are fewer and much more simple. 
Position and locality: Shaly lhmestones of the Chester group, 
near Grayson Springs, Ky. 
KIRKBYA (? BARYCHILINA) CosTATA, (McCoy). 
Plate XVPLT, Pigs) 2a ao. 
Kirkbya costata (McCoy), Jones and Kirkby, Ann. Mag. Nat. 
Hist.,’ Ser. 5; Vol: XV, Plate Vi Migs! 137 
Size: Length, 2.02 mm.; height, 1.06 mm.; thickness of one 
valve, 0.5¢ mm. | 
Of this species I have seen only a single valve. This does not 
agree exactly with the valve figured by Jones and Kirkby (it is 
longer), but the costate ornamentation is so nearly alike in the two 
that I feel reasonably certain of their identity. When it comes to 
the generic relations of the species I am much less confident. 
The general aspect of the valves strikes me as different from that 
of Kzirkbya, and more like Barychilina. If the species really 
