from the Cincinnati Group of Ohio. 425 
shallow marginal groove; eyes comparatively large, situated 
full half their antero-posterior diameter from the posterior 
ins of the cheeks, and elevated somewhat above the 
height of the glabella, truncato-subconical in form, the visual 
surface curving around so as to form about three-fourths of 
at its base; lenses of comparatively moderate size, 
showing about seven in a vertical row at the middle, and twelve 
or fourteen in the longest oblique rows. Surface of anterior 
lobe of — showing small, obscur egranulations; other 
e cephalic shield nearly smooth, or less distinctly 
Yr. 
Thorax unknown. A pygidium found in the same associa- 
e 
characters, there is very little reason to doubt that they belong 
to the same trilobite. 
l us 
differs materially ; i i f the 
materially in having the posterior lateral angles 0 
cephalic shield’ produced io oe spines, instead of merely 
amtinating in broad, rounded, wing- x 
the eyes proportionally shorter, and more remote from the 
Posterior Margins of the cheeks, as well as much more curved 
‘round, than represented in the figures of the New York species. 
