1895. ] NEW YORK ACADEMY OF SCIENCES. 139 
This form differs from Agraulos in the narrow front to the 
middle piece of the cephalic shield and in the long eyelobes, as 
well as the oblique direction of the facial suture, taken as a 
whole. From Holocephalina it differs in the larger free cheeks, 
the narrow space between the sutures in front,and by the length 
and position of the eyelobe. From both genera it differs by its 
long glabella, which, though but faintly indicated on the surface 
of the shield, can be traced. 
PROTAGRAULOS PRISCUS, n. sp., Pl. ix., fig. 1. 
Only the middle part of the head shield is known; this is 
rather flat,and is moderately arched down at the sides and front. 
Front margin with a faint, narrow rim; the front area on the axial 
line is half of the width of the glabella at its widest part; the 
middle piece of the head is narrow between the sutures in front. 
Glabella one-fifth longer than wide, obscurely marked off from 
the cheeks, except in the posterior half; dorsal furrow scarcely 
visible except near the back of the shield. Occipital ring more 
than twice as long as wide, separated from the glabella by a faint 
furrow. Fixed cheeks long, narrow, moderately arched; eye-- 
lobes scarcely raised above the surface of the cheeks, nearly 
as long as the glabella. 
Sculpture. The surface appears to be minutely punctate, and 
has small scattered tubercles. 
Size. Length of the middle piece of the head 10 mm.; width 
in front 6 mm.; at the eyelobes 12 mm. 
Horizon and locality. Sandstones of the middle part of As- 
sise 3 at Hanford Brook. 
A few heads of the trilobite have been found; the form is such 
that imperfect examples might easily be mistaken for the py- 
gidium of a larger trilobite, but the depression in front of the 
eyelobes, though shallow, indicates a head shield. This de- 
pression is continuous with the dorsal furrow, turns outward 
and downward to the corner in front of the eyelobe, and by 
throwing the front area of the shield in connection with the 
glabella gives to the axial ridge of the shield a pseudo-club- 
shaped glabella like that which is found in the embryonic tests 
of Conocoryphe, Liostracus and Ptychoparia. 
ELLIPSOCEPHALUS, Zenker. 
Trans. Roy. Soc. Can., vol. xi., p. 103. 
ELLIPSOCEPHALUS GALEATUS PI. ix., figs. 4 @ to g. 
Trans. Roy. Soc. Can., vol. xi., p. 103., pl. xvii., figs 7 @ to e. 
