New and Little Known American Paleozoic Ostracoda. 125 
ginal region is simply swollen and rounded off. The loop-like dorsal 
elevation also is situated a little farther forward. 
size; Length, o.7 mm.; height, 0.4 mm. 
Position and locality: Rare in the lower shales of the Cincin- 
nati Group at Covington, Ky. 
BEYRICHIA (? PRIMITIA) PARALLELA, Ulrich. 
Flate X, Figs. 15a, 6, ¢ and d. 
Primitia (? Beyrichia) parallela, Ulrich, Contr. to the Micro. Pal. 
of the Cambro-Silurian Rocks of Canada, Plate II, p. 51, 1889. 
This species having been incorrectly illustrated in the work 
cited, and new and better specimens having been collected since 
from equivalent strata in Ohio and Indiana, new figures and 
remarks are now offered so as to complete the publication of the 
species. . 
Fig. 15@ represents a nearly perfect left valve from near the top 
of the Cincinnati Group, at Richmond, Ind. It shows the strongly 
elevated posterior border,* less prominent and more rounded ante- 
rior margin, and a nearly distinct prominence in front of the 
sulcus that may well be regarded as representing the median lobe 
of eyrichia. ence the change in nomenclature proposed 
above. 
The original specimens were from rocks equivalent to the upper 
beds of the Cincinnati Group. Others were obtained from shale 
washings at Oxford, Ohio. 
EURYCHILINA, Ulrich, 1889. 
This genus, together with two species, &. reticulata, the type of 
the genus, from the Trenton shales of Minnesota, and Z. manito- 
bensis, from rocks supposed to be equivalent to the upper beds of 
the Cincinnati Group, is described in ‘‘ Contributions to the 
Micro-Paleontology of the Cambro-Silurian Rocks of Canada,” 
Part II, p. 52. The generic description given there is as follows: 
‘¢ Valves semicircular, sub-oval, or nearly circular. Dorsal line 
straight. Generally with a well-defined sub-central sulcus and a 

* In the original work on this species the term ‘‘ anterior’? was applied to 
what I now regard as the ‘ posterior ”’ extremity. 
