202 PALEOZOIC PALEONTOLOGY. 
Jersey. Ata later date Clarke published an illustration of a speci- 
men of the species from the type locality, but this figure shows much 
larger eyes than could have been present in the New Jersey specimen 
and the lateral margins of the median lobe of the glabella are not 
straight and parallel as in the specimen under consideration. The 
marginal border continuing around the anterior margin of the head, 
which is shown in Clarke’s figure, is not present in the specimen from 
New Jersey. By reason of these differences it seems possible that the 
New Jersey trilobite should be considered as a distinct and unde- 
scribed species. 
ENCRINURUS TRENTONENSIS Wale. 
Plate XV., Figs. 26-27. 
1897. Encrinurus trentonensis Walc., 31st Rep. N. Y. State Mus. 
Nat. Hist., p. 68 (p. 14 of reprints). 
Description.—Pygidium subtriangular in outline, length and breadth 
nearly equal; the lateral margins straight or slightly concave; the 
posterior extremity sharply rounded or subangular. “Axis narrow, 
with tapering sides, terminating within the posterior margin of the 
pygidium, with about twenty-five narrow segments in the larger indi- 
viduals. In the best-preserved specimen observed the first, fourth, 
seventh, eleventh, fiftenth and nineteenth axial segments each bear a 
low, blunt tubercle at the median line of the axis, while some of the 
intertubercular segments become fainter and even almost obsolete in 
the middle. The plure curve abruptly to the lateral margins, es- 
pecially posteriorly, and are marked with nine or ten ribs on each 
side, besides a median rib, which joins the posterior extremity of the 
axis with the posterior margin. The lateral segments curve back- 
ward distally, so that the outer portion of the anterior ones and nearly 
the whole length of the posterior ones is directed backward, the most. 
posterior ones having a direction nearly parallel with the axis. 
An average adult specimen of the pygidium has a length of 9 mm..,. 
with the breadth the same. 
Remarks.—Aside from the pygidia, which are fairly common in the 
upper portion of the section at Jacksonburg, only a few fragments 
of glabelle and cheeks which probably belong to this species have: 
been observed. These fragments are all strongly tuberculate through- 
