116 Cincinnati Society of Natural Fistory. 
BOLLIA PERSULCATA, (Ulrich). 
Beyrichia persulcata, Ulrich, Jour. Cin. Soc. Nat. Hist., Vol. II., 
NO:41;.p: 12,021 VEE ones toro: 

Fig. 3. Bolla persulcata, Ulrich ; lower beds of the Cincinnati Group, 
Covington, Ky. a, left valve of the usual form, x 20; 4 and 
c, ventral and posterior views of same ; d, right side 
of another carapace presenting slight 
differences, x 20. 
This specimen is a true member of the group of Ostracoda dis- 
tinguished in 1886 by Jones and Holl as Sola. The posterior 
half of the horse-shoe ridge has its dorsal extremity separated as a 
rounded node projecting, like the other ridges, a little beyond the 
dorsal edge. Its bent ventral portion is thin and depressed, 
so that when the valves are attached to slabs, as is the case with 
the original examples, they usually appear as simply traversed by 
four slightly curved vertical ridges. In free examples, however, 
the true characters and forms of the ridges are shown as in the 
above figures. 
Size: Length, 0.77 mm.; height, 0.45 mm.; thickness of closed 
carapace, 0.43 mm. 
Prof. T. Rupert Jones lately referred an incomplete valve of this 
species to his Bevrichia buchiana, adding an interrogation point.* 
He admits that his specimen is ‘‘not well preserved,” but over- 
looked, what I am confident he will find to be a fact, that the pos- 
terior lobe or ridge is broken away. Adding this ridge the valve 
would be identical in every particular with ordinary specimens of 
Bolha persulcata. His example, when complete, must have been 
more elongate than my original figure of the species (oc. cet.), and 
this fact probably misled him. But that figure is incorrect in its 
proportions, the height being too great, causing the valve to appear 
semi-circular, when it is really sub-oblong. 

* Quart. Jour. Geol. Soc., Vol. XLVI., p. 16, Feb., 1890. 

