108 
PALEONTOLOGY OF NEW YORK. 
The doublure is strongdy rounded and incurved, somewhat excavate at the 
genal angles, sharply convex and ridged upon the genal spines. Its surface is 
marked by longitudinally parallel, lamellose lines. 
Distribution. Upper Helderberg group. Corniferous limestone: Columbus, 
Ohio ; Falls of the Ohio, Ky. 
Pkoetus Verneuili. 
PLATK XX, FIGS. 18, 19. 
Proetus Venieuili, Hall. Descr. New Species of Fossils, etc , ]i. 73. 1861. 
ProHus Verneuili, Hall. Fifteenth Kept. N. Y. State Cab. Nat. Hist., p. 101. 1862. 
ProUus Venieuili, Hall. Illnstrations of Devonian Fossils, jil xx, figs. 18, 19. 1876. 
The cephalon and thorax of this species have been observed only in a con¬ 
dition too incomplete for description. 
Pygidium short, nearly twice as wide as long; outline sub-elliptical;-surface 
convex axially, laterally depressed. 
Axis having one-third the width of the shield on the anterior margin, 
strongly convex, tapering rapidly to a blunt termination close upon the 
posterior border; bearing nine to eleven annulations, which have a retral 
bend over the axial line, where the first three or four are thickened and 
nodose. 
The pleura are Hat for a short distance, thence abruptly deflected and bear¬ 
ing seven or eight annulations which are faintly grooved. 
The border is broad, abruptly sloping for one-half its width, and near its 
inner edge bears a row of conspicuous nodes, which correspond in number 
and position to the annulations; outside of these the margin is smooth and 
concave. 
The best preserved specimen of the pygidium has a length of 4 mm., and 
a width of 7.5 mm. 
This species is well defined by the characteristic row of nodes upon the 
border, a feature which has been observed in many specimens and is undoubt¬ 
edly persistent. 
